M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: fiftytakedowns on February 11, 2011, 01:07:50 AM
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IS there any way to isolate whether this is a Fuel issue, a Spark Issue, or an electrical Issue?
Im planning to attack this in a couple ways this weekend:
Here are some Videos of how it runs:
http://www.youtube.com/watch?v=Eu5npniUyl4
http://www.youtube.com/watch?v=NF3NEp_dnX4
the sensors Checked out pretty good CPS had a like 650 ohm reading while the camshaft sensor was like 1300 ohm.
it's acting like its not getting fuel. Im hoping there isnt some fucked Wiring somewhere. and I added and extra ground between the shock tower and the intake plenum.
Any Ideas?
I am getting two different ECU readings
Of my MARK D chip ECU and its spitting out a 1271 code
off the stock ECU no chip Im getting a 1244 code
the Stock ECU has LESs of a problem than the Mark D one, but it still is pretty bad and NOT driveable.
So I do have a SPARE DME.
and its been even more frustrating now, as I am leaning towards fuel problem now.
I'll be driving, the car will be going fine, and after 30 seconds of driving, it will do agressive sputtering, and nearly impossible to drive. my narrowband gauge is going all over the place, but moving to the lean area. I think... But If I take out the ECU and put it back in, it resets and goes back to normal. until 30 seconds are over.
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As far as I see its somethin electrical man, should be an easy sensor fix. When you let go of the clutch it smooths out just because the engine being under load causes the engine to turn, instead of being forced to turn by combustion.
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As far as I see its somethin electrical man, should be an easy sensor fix. When you let go of the clutch it smooths out just because the engine being under load causes the engine to turn, instead of being forced to turn by combustion.
Did some sensor Testing:
Coil 1: WAs Sparatically Changing Ohm Levels:
from .03 to .05
Coil 2: .015
Coil 3: .015
Coil 4: .015
These were the coils Off of a Coil on Plug conversion, not sure if that makes a difference.
AFM:
got a consistent reading between pins 3 & 4 to 3.94V through -.06V
Between pins 1 & 2 : 3.8 V
TPS:
At idle between Pins 1 & 2 4.3V
Full throttle: .96V
Between pins 1 & 3 5v
Between pins 2&3 at Idle .62 V
full throttle: 4.0V
I may have done some testing wrong though, I just sort of stuck in the gauge and read values.
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Double check those coils. If you have one off it'll overheat the DME coil drivers & eventually kill the DME.
COP packs are difficult to test, you may have to take them to a shop for testing. I'd attempt to swap that low resistance one out. DVMotorsports had the same trouble with his, it killed the DME. I'll see if I can find the thread after I get the kids on their school bus.
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That sounds like how fuel pumps die.
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How doyou know if the DME is dead, They have been spitting out the same codes for quite a while.
I was wondering if a fuel pressure regulator would have anything to doi with these problems
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If the DME dies the car won't run. The trouble with a bad coil pack is that it won't protect the DME's coil drivers. The pack & the driver work as a team. If the pack dies it will eventually take the driver with it...too much current flows through the DME & cooks the driver. I'm not sure what kind of code this would set, if any.
The coil drivers are just four big transistors mounted in the DME case. If this is what's causing your trouble, even if you pull the dying coil pack & swap a known good one in, the driver is damaged & it won't run right until you replace or repair the DME. Those packs use a lot of juice and the drivers will overheat if the coil resistance is out of spec.
I'd start eliminating problems instead of just guessing. Ask if you can borrow a fuel pressure tester to eliminate that whole system. You could buy one too, HF usually has them for <$20. You don't need a pro unit (as long as it can measure pressure over 50psi), something cheap like this will do:
http://www.harborfreight.com/fuel-injection-pump-tester-92699.html
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Good news: its not the coils.
got some new ones, and they didnt change anything.
I put some plug wires in, and then had the coils on separate, and then I disconnected the plugs wires, and there was still spark jumpin between the coil pack and the plug wires.
what Is really odd is how if I disconnect the DME and plug it back in again, the problem goes away temporarily.
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Glad it's not the coils, one thing eliminated. So let me ask a few more questions, I'm not 100% on this one.
Does the problem go away only when the DME is cold?
Both DMEs through different codes?
Did you test the O2 sensor?
Makes me think something is way out of whack when the car leaves open loop (the warm-up & WOT cycles). and switches over to closed-loop (normal running with a warm engine). O2 and temp sensors are the culprit on that one...they both might make the car run really rich but should throw a 1213, 1221 or 1222 code. Coolant temp sensors should throw a 1223, but I've never seen nor heard of that happening.
Your O2 sensor is going all over the place, are you sure it's good?
The other opinion I have is that the DME has a bad coil driver as I've mentioned before...if it's overheating the DME may be going. But if you've been swapping two DMEs and having the same symptoms I'd suspect that's not the case.
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Glad it's not the coils, one thing eliminated. So let me ask a few more questions, I'm not 100% on this one.
Does the problem go away only when the DME is cold?
Both DMEs through different codes?
Did you test the O2 sensor?
problem is worse when Car is cold
Dme temperature seems to not matter.
Both DMEs throw different codes.
O2 sensor has less than 10,000 miles on it.
when I plugged in the thing up top (hot start plug) it Seemed to help a little, but then problem would come back
Makes me think something is way out of whack when the car leaves open loop (the warm-up & WOT cycles). and switches over to closed-loop (normal running with a warm engine). O2 and temp sensors are the culprit on that one...they both might make the car run really rich but should throw a 1213, 1221 or 1222 code. Coolant temp sensors should throw a 1223, but I've never seen nor heard of that happening.
the CEL doesnt come on!
Your O2 sensor is going all over the place, are you sure it's good?
It's a narrow band so it only gives a general reading.
The other opinion I have is that the DME has a bad coil driver as I've mentioned before...if it's overheating the DME may be going. But if you've been swapping two DMEs and having the same symptoms I'd suspect that's not the case.
I know it's pretty frustrating
[/QUOTE]
Took it to a mechanic, he wasnt giving full attention, but He heard it.
mechanic says its a misfire, where should I check next?
BTW i unplugged the camshaft sensor and it changed nothin, same synptoms.
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I'm stumped myself. You've been all over that engine. Let me think on it for a while.
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I'm stumped myself. You've been all over that engine. Let me think on it for a while.
Thanks man, I appreciate your effort, Im getting really Frustrated, and Not to mention it's parked in front of the GF's house, and they want it out!
Once I finish the e30 I can go back to working on my Turbo 2002 which is liek NEARLY done!!
here is the link to my 2002 Turbo Build thread which I will attent to once I finish this e30
http://www.bmw2002faq.com/component/option,com_forum/Itemid,50/page,viewtopic/t,346632/highlight,/
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Fuel pressure gauge would tell if its the pump.
I've seen fuel filter cause this exact problem and no matter how new they are it only takes 1 tank of bad gas to wipe one out....
Make sure your head has a ground strap to a good earth. COP kits need good circuits on the ground side to function correctly. The new non metal head gaskets prevent good electrical contact to the block sometimes.
How old are the injectors? THey can get sticky when hot and grungy.
Good Luck
Dave
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Fuel pressure gauge would tell if its the pump.
I've seen fuel filter cause this exact problem and no matter how new they are it only takes 1 tank of bad gas to wipe one out....
Make sure your head has a ground strap to a good earth. COP kits need good circuits on the ground side to function correctly. The new non metal head gaskets prevent good electrical contact to the block sometimes.
How old are the injectors? THey can get sticky when hot and grungy.
Good Luck
Dave
I was getting a consistent 45 PSI at one of the fuel lines and 55 if I disconnect the FPR . I only tested one, but I figured the return line wouldnt have 45 PSI anyway.
I replaced the ground strap that goes from the Frame to the like engine mount arm thing. I have another ground strap that I attached from the shock tower to the intake throttle body( I figured it would get to the head?). There Is a third ground wire that appears to be coming from the Firewall where the battery would be, and it's grounded at a spot right there (clean contact)
I have a spare stock set of injectors, if all else fails I'll swap them in. as well as the TPS that is on that spare throttle body.
Is it possible that the coils are grounding out to the COP bracket? I cant quitte understand why its throwing a COIL #1 code in one of the DME's and the other DME is throwing a Camshaft Sensor Code.
I also did a smoke test and found NO vacuum leaks or any smoke protruding.
The car did sit for about a month while I did the Timing chain job.I just filled up the tank yesterday. But what Is extremely weird Is why would the problem go away temporarily If I unplug the DME and plug it back in again?
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When you unplug the DME it resets to a standard map, then as the engine runs it attempts to compensate for what it perceives as the optimum settings.
The newer pump gas SUCKs for storage, If the tank was below 1/2 its very possible the fuel went bad. The fuel should have a light sharp smell not a heavy varnish smell, often the exhaust will smell real odd if the fuel is dodgy...
It sounds absolutely crazy but If the head itself is not really grounded directly to the battery neg You can have weird ground paths in the motor. I've had a handfull of race cars where 2" of ground strap grounding the head to the block has fixed weird ignition problems, as well as bad DME grounds... Its the reason the rice tuners have the ground spiders under the hood of their turbo cars, makes up for the shoddy factory wiring...
You could also have a thermal issue as someone pointed out, crank sensor or cam sensor that is freeking out when warm. probably tests good when cold.
Good Luck.
Dave
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When you unplug the DME it resets to a standard map, then as the engine runs it attempts to compensate for what it perceives as the optimum settings.
The newer pump gas SUCKs for storage, If the tank was below 1/2 its very possible the fuel went bad. The fuel should have a light sharp smell not a heavy varnish smell, often the exhaust will smell real odd if the fuel is dodgy...
It sounds absolutely crazy but If the head itself is not really grounded directly to the battery neg You can have weird ground paths in the motor. I've had a handfull of race cars where 2" of ground strap grounding the head to the block has fixed weird ignition problems, as well as bad DME grounds... Its the reason the rice tuners have the ground spiders under the hood of their turbo cars, makes up for the shoddy factory wiring...
You could also have a thermal issue as someone pointed out, crank sensor or cam sensor that is freeking out when warm. probably tests good when cold.
Good Luck.
Dave
I had around 2 gallons in the tank, that was stored for around a month. then I put in 20 dollars worth 2 days ago, and have been going through that trouble shooting.
I just grounded the head with a cable to the chassis, Ill ground the head to the block with another ground cable.
Do you think I should throw in some seafoam in the oil or gas? or replace the injectors? I have another set of injectors.
The car doesnt drive at all ONLY idles when cold, and when warm it just misfires occasionally.
I have a spare coolant Temp sensor Ill throw in to see if that helps any. Whats teh sensor next to the Coolant temp sensor? isnt that just for the Gauge?
Is it possible that the COIl on Plugs coils are grounding out on the Plate itself? I did notice that Cyl #1 had weaker spark than the others, but IT was getting 12Vs and it wasnt the coils fault. I also checked out the resistances between the DME pinout and the Coil wire and it seemed to check out OKAY.
WTF.
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I've tried mixing 20 gallons of brand new premium with 3 gallons of tired stored gas, ended up draining the tank. The rotten fuel just kills the good fuel.
The guy distributor buy race fuel from says if the air in the tank is more than 10% of the volume the odds are the fuel will go stale. Stabil fuel stabilizer is a good thing in a project vehicle.
I'd unhook the coil connections and use a ohm meter to see if the parts that are not supposed to be grounded aren't. I thought the main core of a coil is usually grounded, it should not effect function, the windings are the weak point, if they short to ground you going to lose spark,the usual cause of coil failure is the insulating varnish on the winding getting old and starting to leak current across to other windings. as long as the winding to frame ohm reading is in spec and the winding resistance is in spec your usually OK.
Dave
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See what was really interesting was that I was not having any trouble getting good spark from the coils, whichever coil was hooked up to number one was having a weaker spark than the other three. I checked this by pulling out all four coils and attaching them to spark plug wires which were attached to the corresponding cylinders. then I would pull the plug wire from the coil, and observe the spark arching between the coil and the plug wire. It was clearly a weaker color on cyl #1 no matter which COIL was attached.
That being said, the connector was getting a sufficient 12V to both grounds.
-Im not sure I understand how I check coil connections to places that are vs arent spupposed to be grounded.
Im getting really upset/depressed/ and frustrated with this car, I put in another 14 hours today replacing the Temp sender, the Coolant temp ssender, soaking the injectors in carb cleaner, pulling all the wires, checking for fraying checking the box under the intake plenum. testing the resistances between the DME and the coils. I also attached a large cable between the head and the block. NO avail.
What is sounding like the car is getting No fuel at all, the narrowband starts showing it going lean. I dont know what is goin on.
It's been 2-3 years having this car. and after this timing chain rebuild I did It's not even driveable. and I even double checked the cam timing. What the fucking fuck Im about to just pull this engine and go 24V or Just part it out, or sell It. Im really really feeling down.
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Anyone who finds out the problem Will get a VDO gauge set that I have. as incentive.
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New hint:
I have ECu1, and ECU2.
-Start with ECU1 drive car for about a mile, misfiring occurs, first with one like quick hesitation, then it progresses to get worse, and worse.
-Pull over. pull out ECU 1, put in ECU2, (ECU2 still displays the same problem right off the bat,), pull out ECU2, put in ECU1, problem goes away until about a mile of driving...
-repeat.
OTHER symptom that may tell a lot about the problem.
-> If I can luckily Downshift to get the engine to be past 4500RPM it will not occur up there. Only misfires between 2k-4500 RPMS. IF I decelerate under 4500 rPM it will still misfire.
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I don't know if this is related...sounds like it might be...I found a link over at e46forums about Bremi packs failing due to internal insulation failure. Mine are all Bremi, makes me worry a bit. The odd thing is that the BMW TSB recommended changing all of them...not one at a time, like when the Bosch coils fail.
I know you tested with another set of coils, but I'd probably try the original external coils & wires if you still have them. I have three known good coils from an e30...if you need them for testing I'll send 'em along for postage. $5 gets you a flat rate box...send them back when you've fixed it. I wish I had all four, but I sent one along with my spare DME to another member who had similar problems.
Here it is, along with a few others:
Bad DME & coil (http://m42club.com/forums/showthread.php?t=10406) thread
Bad motor wiring harness (http://www.m42club.com/forums/showthread.php?t=11953) thread
Bad #3 wire (http://www.m42club.com/forums/showthread.php?t=10504) thread
There is a date stamped on the coil for production week/year. The effected Bremi coils are 42/2002 or earlier, or in the range from 01/03 up to 24/03. Mine are all older than 2002, so I'll be on the lookout for this too. Likely they were pulled from an M70; nobody who owns a newer BMW will touch the Bremi coils so they're cheap. IIRC, the early Bosch units were also pretty bad, the Bremi's were supposed to fix the trouble.
It doesn't fit your symptoms exactly, but it's close. Any chance you'd take those coil packs to a dealer to have them tested? Know anyone with a GT1? If you were closer I'd hook you up with my BMW mech buddy...I try to avoid dealers as much as possible, but there's a place & time for everything. Not that many BMW dealers will touch anything older than 2000, but it might be worth your time. I hear your frustration, I hate when I can't get a car or bike running right. But trust me, once you get this car running right you'll be glad you did.
http://forum.e46fanatics.com/showthread.php?t=226581
SITUATION
Engine may run rough and "Check Engine" light is illuminated. Misfire faults are stored in DME control module.
CAUSE
Reduced ignition firing power of BREMI coils due to coil internal insulation deterioration.
CORRECTION
Follow the appropriate Test Plan from DIS Plus/GT1.
If BREMI ignition coil is found to be defective, and the production date stamped on top of other coils housing's is
42/2002 or earlier, or in the range from 01/03 up to 24/03 all six coils must be replaced . For replacement instructions
refer to RA 12 13 511 found in BMW TIS.
Only coils manufactured by BREMI are affected. BREMI coils are easily recognizable by the all black, shiny housings.
Bosch coils, which can also be fitted in M roadster/coupe and M3 vehicles with S54 engines, are not affected and should
NOT be replaced as a set. Bosch coils have a silver, aluminum housing.
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Obviously it's a fuel issue. Its getting fuel Cut for some reason.
(http://dl.dropbox.com/u/11819570/Photo%20184.jpg)
spark plug is speckled Lean hardcore.
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What are the Three relay boxes, I think the far right one might be the issue, is there a way to jump it?
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If you're looking at the firewall from the driver's fender like I tend to do, they're the main motronic relay, FP relay & O2 heater relay.
You can jump it with a wire from terminal 87 to 30 on the socket. It's a 5-pin relay, when it's not powered pin 30 shorts to pin 87a. When it's powered it'll short pin 30 to 87 instead. It should turn off fairly quickly after the car starts though. Once the O2 sensor gets up to temperature the DME turns the heater off, since the exhaust gas is hot enough to keep the O2 sensor accurate.
Makes me wonder why your car doesn't like an unheated sensor...maybe it's bad? I thought you'd recently replaced it?
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If you're looking at the firewall from the driver's fender like I tend to do, they're the main motronic relay, FP relay & O2 heater relay.
You can jump it with a wire from terminal 87 to 30 on the socket. It's a 5-pin relay, when it's not powered pin 30 shorts to pin 87a. When it's powered it'll short pin 30 to 87 instead. It should turn off fairly quickly after the car starts though. Once the O2 sensor gets up to temperature the DME turns the heater off, since the exhaust gas is hot enough to keep the O2 sensor accurate.
Makes me wonder why your car doesn't like an unheated sensor...maybe it's bad? I thought you'd recently replaced it?
I put in a different relay box that I had laying around and it seemed to fix that problem... and It was the box closest to the Fuse box, the 4 pinned one.
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That's the main relay...guess it was overheating & partially killing the DME power. Weird. Good to hear that you're getting results. Good thing you have a spare!
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what do you mean exactly when you say you cover the intake so you create a vacuum?
also how hard was it to replace the relay box? or do you mean you pulled one of the relays?
I pulled one of the Relays that sit next the fuse box. the three up top that are covered by the plastic harness cover.
I create a vacuum by putting my hand over the front of the AFM. then opening hte throttle with the other hand. you can see the intake bellow collapsing, and the noise of a leak near the intake. I cant find it.
Here are Some driving symptoms:
occasionally the stuttering will start occuring between 2-3K rpm, and when It does, here is wat the car does when that happens:
IF I floor it I can sort of stutter through the missfire until i get out of the zone, then past 3k rpm and then pulls hard to redline. If I pull off the gas, but downshift back into the zone without letting the car cruise at a lower rpm for a bit it will stutter if I get back into that zone.
If I put it in nuetral and let the car idle for a second, or two, I can slowly (without any load) accelerate through that zone, and then it goes away and I can drive normally until it shows up again, usually within 5 minutes.
the event only shows up UNDER LOAD! or cruising, USUALY cruising. Never at WOT, or SMashing through the gears.
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Have you checked over the whole mess of emission hoses to see if any have split, have a hole in them, or are simply disconnected? Just my 2 cents.
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Have you checked over the whole mess of emission hoses to see if any have split, have a hole in them, or are simply disconnected? Just my 2 cents.
I doused everything all hoses, gaskets ETC in WD40 as well as Carb cleaner to see if it would change the idle speed or make anyhting noticeable and I had no avail. :(
also, after letting the car cool down completley, It still has the cold start problem, where it is impossible to drive when cold, It will only idle. merely bogs down off the bat
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maybe a large vacuum leak near the #1 cylinder. i personally think that finding vacuum leaks with other products that are supposed to rev the engine is difficult. Instead i pressurise the intake (under 5 psi), listen and then spray soapy water where the sound seams to come from. Unless it's a lot of vacuum leaks, pretty sure they aren't the culprit for your missfires.
Just for the heck of it, did you try other spark plugs?
list of new/swapped parts?
how are your plugs right after the missfire? indicate lean/rich situation? oil fouled?
If i read right, this started to happen right after your timing chain refresh?
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They are VERY VERY VERY lean
(http://dl.dropbox.com/u/11819570/Photo%20184.jpg)
the shop has smoke tester I'll try
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all plugs are like that? just #1? or #1 and #3 ??? IIRC, cyl injectors 1&3 are linked
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I'll pull the plugs this friday and see what I get
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Did some more thinking, hopefully it can help us all figure it out.
Cold start -> cuts fuel when attempting to rev up, only can idle until reaches operating temp.
When driving --> occasional misfire most likely due to fuel cut or loss at 2k-3k Rpm
Which sensors would affect a fuel cut misfire during that revband no matter how hard pedal is pressed, could it be pair of injectors causing the jerking?
Vacuum leak would cause a leAn condition not sure if it would be so violent and rpm specific.
An erratic icv signal would cause an interesting shift in air , however it would tell the afm to enrich mixture. What would cause an erratic signal possibly?
Should I plug all possible vacuum lines Adjust the throttle to supplement for icv blocking?
Can relays switch off and on erratically? Such as the fuel pump relay? Any specific wires I cab check resistance of? What should I look for ? What values?
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Yes, relays can sometimes cut out. If those are your original 20-yo reays you should replace them as preventative maintenance.
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Alright, Ive got some plans for this coming weekend of tackling the problem, both the Cold start one, as well as the fuel cut once warm.
This thread gave me some Idea of possibility:
http://www.r3vlimited.com/board/showthread.php?t=89925&highlight=Fuel+cut
what I am going to do Is jump the Fuel pump, becuase aparently I have been jumping the wrong one the entire time ? Is the fuel pump one the five pronged or the Four pronged? my 5 pronged relay looked beat to shit when I pulled it so I cleaned the terminals and re-installed. (that being said, Does it matter where I get the relays? napa auto or does it need to be OEM?)
Then I was going to Smoke test for Vacuum leaks again. because I am hearing a hissing and especially a whistling when I create more vacuum by covering the intake. Then I will replace the lower Intake mani gasket. and fuel injector o-rings.
My Boot Is cracked in a bunch of places but I dont think it's leaking any air as light doesnt shine through. or the vacuum gauge doesnt fluctuate as I move it around. Either way I will replace it once I can find this problem.
I also Have a vacuum gauge to help me diagnose. (however I should use it)
- Seafoam the Gas, Intake, and Oil.
- swap in third ECU and check for codes
- See if all plugs look lean. or if a pair etc etc.
--> another thing I was wondering was I have been Testing my crank and cam position sensors. Does it matter If they Are cold or Warm or both? What values should I expect When I do that?
Although I highly doubt it's a wiring issue, because I dont see any corrosion Etc. around wires, Is it difficult to exchange the engine wiring harness?
(although a silly question) I want to retest the coils. but I am not sure What ohm setting to put onto the multi-meter, They are sparkin thats for sure, just wanted to be sure I was doing it right.
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All I can say is holy crap dude! I would have shot the car a loooooong time ago! Nothing would satisfy me better than burning mashmallows on it on a cold night. Cudos to you for hanging in!
If i wer you, I would just start at one thing at a time. Seems like there are too many things to jump at. I would rebuild (in my mind mostly) the WHOLE fuel system. I would check it from azzhole to elbow. Replace what does not look right. Check everything fuel related, that includes EVAP parts. After that move to the next thing. Break down the electrical into section. Sensors, grounds, DME, spark........ Go over each one meticulously, hot, cold, with cherry flavor, ice tea, whatever, pretend like your BMW testing grounds! Throw the sensors in the oven and test, freezer over night and test etc. I know your gonna cover a lot of same ground, but, check and document so you can move on and have a record.
It does sound like fuel or spark issues, duh, but, also recheck the basic condition of the engine, like compression and leakdown too.
One thing, and I may have missed it, is I did not hear anything about the TPS, MAP or MAF??
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I think I thought of a Janky solution so at least I can drive the car and move it from my girlfriends (temporary fix).
If there is a signal somewhere telling the car that it needs to cut the fuel therefore fuel pressure is dipping causing the jerking, i am thinking about eliminating an entire pathway of wires. and signals.
What I can do is attach a switch to have teh fuel pump running or not, so at least I can elimnate the COIL POsition sensor pathway as a posibility, and eliminate a chance that maybe the CPS is sending a bad signal for fuel, or maybe the DME is getting a bad signal etc. etc.
I could use this so atleast I can move the car and use it until I can find another solution. Does anyone see a problem with this?
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OK, I'm going to take a totally different tack on this, and I might be crazy off base.
What about timing? How much have you driven it since the timing chain swap? Is it possible that you are off one tooth or a tooth is missing or something crazy like the tensioner not always providing tension?
Ignore me if you've been driving it for a while, but I was just giving a bit of input b/c based on what I've read here, all this started after you did the timing refresh and logically that tells me something is wrong there...
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OK, I'm going to take a totally different tack on this, and I might be crazy off base.
What about timing? How much have you driven it since the timing chain swap? Is it possible that you are off one tooth or a tooth is missing or something crazy like the tensioner not always providing tension?
Ignore me if you've been driving it for a while, but I was just giving a bit of input b/c based on what I've read here, all this started after you did the timing refresh and logically that tells me something is wrong there...
NO I totally see eye to eye with you.
one thing I was thinknig that it did have something to do with timing. however, the car will run very well for little bits of time. the problem is very very random almost no method to madness.
that being said I have checked and re-checked cam timing to the best of my ability. if you see in another thread I just posted in general topics (finding TDC). I go over my methods.
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Did you even verify with a pressure gauge it was losing fuel pressure?
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so I just did a quick test right now to see if the crank position sensor was possibly sending a (bad) signal to turn off the fuel pump when the car is cold, thus causing some bogging, and agressive misfiring. (some popping in the exhaust as well)
I didnt hear any distinct noises signaling the pump was stopping it's action, suggesting that maybe it isnt the fuel pump, or the fuel pump relay, or maybe the CPS sending a bad signal.... just a thought.
Also Ryan was awesome enough to send me a spare (third ECU) to test my car with. NO luck with the DME but It did kick out a 1244 code which one of my other ones were kicking out as well.... that is the camshaft position sensor I believe.
is the 5 pronged relay on the harness the ECU relay? it was pretty old and the terminals looked burnt.
Something peculiar I discovered however was that when I was pushing and holding on the throttle and the car was misfiring was the ligghts were getting and flickering much brighter than normal, and the pump was also pumping a bit harder and louder.
Did you even verify with a pressure gauge it was losing fuel pressure?
I did, but not while it was making the hesitation or missfiring. it was intermittent and I couldnt get it to to it again at that time. However when I was testing at that point I was getting a solid 45 PSI. and 50-55 when I disconnected the FPR.
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double post
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When you did the test with the lights getting brighter, did you have the COP or OEM coil in there?
I ask b/c that points back to a degree to some of what Dave is saying. That's a bit thin, but a possibility nonetheless.
I'm going to stick with timing, though. How about the tensioner, or a link in the chain that is a bit wonky? I've not had a chance to read your other thread to check your method, but here is my logic:
- Seems like you have good fuel
- Seems like you have good spark
- Since those are the only 2 things technically you need to run, in order for it to run correctly, the above to must happen at the right time, and based on everything you are mentioning in terms of codes; too lean, misfire, etc., that all leads to incorrect timing.
I could be way off base, but it doesn't seem that avenue has been exhausted just yet, and all the parts swapping is more or less chasing you tail. Personally, I'd pull the timing cover off and do some inspecting, but I dunno if you can if it's not somewhere you can work on it.
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I have a little bit of an update:
I spent all day today fuxoring with the car and I took some steps forward and backward. I guess I am back to square one.
But here is some prequel.
I have Three ECU's
Two of em are spitting out 1244 (camshaft sensor) the other one is spitting out a 1271 (coil one) I even was running a different coil in 1271 today. (I had to modify the housing to get it to fit as you may know with the COP's)
one of the 1244's takes a long time for it to start misfiring. It will be running and driving great like nothing's up. then after cruising a little while at a consistent RPM.
I was curious about something, IF it is in Nuetral the Car will rev up like it aint no thing. once some load gets on it, it doesnt like to drive. for example it will do alright in first gear. and if it does misfire even without the load. If i let it chill in nuetral for a minute It's all good again.
I was definitley getting fuel pressure when I heard some bogging as well. I checked it out. IT would be fully bogging/missing while still getting some 45 PSI.
anyone have a PERFECTLY good set of COP coils to use to help me rule out the coils?
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Just had a flash about timing and cam sensor relation... when you put the sprockets back on, did you put the pin from the (exaust) gear at the right spot? that pin triggers the cam sensor and tells the ECU when to send a spark. It might be off by just 1-2 teeth, enough to have a decent idle, but too much to get good performance. valve cover will have to come off and possibly even the upper timing case cover to check.
I have clear pics of the said pin when I did that job, just scroll down a little
http://www.m42club.com/forums/showthread.php?t=7517&highlight=B318m42W
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BOth arrows are pointing up. Im almost positive it's in the right spot I have nearly checked and adjusted 4 times.
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Im never going to figure this out.
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So today I did a sensor test by
driving car.
unplug sensor
drive again.
evaluate.
repeat.
I did that for every sensor:
Camshaft position
AFM
TPS
TPS and ICV
ICV
O2
Every single time it had the same symptoms.
also every time the car would run alright until about a minute or two of driving, then the misfiring would happen.
I also replaced the injectors and FPR with a spare set I had.
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Man, I admire your patience. I think you might have some kind of issue in your wiring harness, but there are a couple of longshot things you could check.
Sometimes the rubber in the crank balancer cracks and allows the balancer to precess or wobble, throwing off the CPS.
Also, the thrust bearing is a weakness and can wear, causing excess crank thrust. It might be possible to throw the CPS signal off if thrust was too excessive.
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So what do i do from here?
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You are seriously going to punch me through the Internets, but I still think you should disassemble the entire front of the car and inspect all things timing related.
All your codes seem to me to be point back to timing and since you just did the chain and such. Maybe the CPS wire is frayed somewhere along the path and arcs or grounds out somewhere? I dunno, but I still just think it has to be this.
So back in my M20 days I did the timing belt, tensioner, etc as part of some regular maintenance. As I should have, I turned the motor over by hand a few times to make sure I had the timing right which I swore I did.
Sure enough, I turned it over and it ran- like butt. It was a merry christmas and I got lucky and didn't blow the head. I took the whole thing apart and re-checked. The second time, it was perfect. So this is why I think it is totally possible that this is the issue for you...
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You are seriously going to punch me through the Internets, but I still think you should disassemble the entire front of the car and inspect all things timing related.
All your codes seem to me to be point back to timing and since you just did the chain and such. Maybe the CPS wire is frayed somewhere along the path and arcs or grounds out somewhere? I dunno, but I still just think it has to be this.
So back in my M20 days I did the timing belt, tensioner, etc as part of some regular maintenance. As I should have, I turned the motor over by hand a few times to make sure I had the timing right which I swore I did.
Sure enough, I turned it over and it ran- like butt. It was a merry christmas and I got lucky and didn't blow the head. I took the whole thing apart and re-checked. The second time, it was perfect. So this is why I think it is totally possible that this is the issue for you...
I understand that, but I really dont need to take it all apart because you can take the cam gears off without taking off the lower sections of the covers. I want to avoid buying new gaskets wasting more money on anything else that I have already looked at. I had both cam gears squared up with the piston at the top of it's stroke. I guess I can go over it again, who knows, maybe the twelfth time's a charm.
Also, why would the computer start misfiring after a little bit of driving then? or cruising, then when it's reset its good again for a little?
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once I figure this out Im going to work at retrofitting some ITBs from a Suzuki so who's got the magic answer
Did some sensor Testing:
Coil 1: WAs Sparatically Changing Ohm Levels:
from .03 to .05
Coil 2: .015
Coil 3: .015
Coil 4: .015
These were the coils Off of a Coil on Plug conversion, not sure if that makes a difference.
AFM:
got a consistent reading between pins 3 & 4 to 3.94V through -.06V
Between pins 1 & 2 : 3.8 V
TPS:
At idle between Pins 1 & 2 4.3V
Full throttle: .96V
Between pins 1 & 3 5v
Between pins 2&3 at Idle .62 V
full throttle: 4.0V
and its doing 19 Mm HG under vacuum at idle
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If you need a decent COP coil I can send you one. Coil 1 seems sketchy, but maybe it's the only one with valid resistance. I cannot recall the proper coil resistance, but i believe it was larger than .015. I'd google the the spec for the M54?? coils and compare.
RE:What do you do now?
Well I would manually check for play in the crank damper. You would have to remove the belts and check for play. I don't know if there is a spec, but it should be imperceptible with your hand. With the belts off you can also rev the engine while looking at the damper to see if it wobbles. You could fit some run-out indicators that should not contact the damper unless to indicate a run-out problem.
As far as the crank run-out, I know there is a spec in Bentley for a disassembled engine, but I don't know if there is one for checking the spec while the engine is in the car. Maybe Bentley has one listed? For this you would somehow press the crank hub towards the block to "zero it out" and then take a measurement. Then have a buddy press the clutch pedal while you measured the amount of forward travel that the crank hub had made.
Unlike the M20 and the S14 engines that I'm used to, these M42s eat the damn thrust bearings and then the wear cuts into the thrust face of the crank, rendering the crank useless. I had to reject 3 used cranks before I found a nice used one for my rebuild because they all had dished-out thrust faces.
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it looked to be spinning straight when I was lookin, which I did check. I didnt have a torque gun so I could only torque it the best I could. I will try to to disessemble it and re-torque with a gun then.
I believe the coils are supposed to be .4-.8 or somethign
what would cause the CPU to spit out those codes though that has me curious.
also, If I wanted to test the wires for corrosion between the terminals and connectors, between ECU and sensor Ig uess.. what values should I look for in ohms?
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Also, why would the computer start misfiring after a little bit of driving then? or cruising, then when it's reset its good again for a little?
You got me on that one. Like I said, perhaps the tensioner is wonky and the computer takes a sec to get the readings? I'm grabbing at straws now and really don't know my way around this motor like Colin, so I'll bow out...
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LOL noooooooo I've lost another mind.
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BTW, I found the M50 coil specs:
You should have 0.4 to 0.8 ohms between the two outer terminals in the coil plug housing. The resistance of the connector boots should be about 1.9K ohms.
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so today I double checked TDC with cams and crank. found notch on pulley etc. etc.
replaced cracked intake boot.
replaced main relay
(both with brand new OEM)
I also took off the crank damper, impacted the mother on and then put on the extra pulleys. I was hoping this would eliminate a vibration that possibly might occur causing screwy CPS signals. just precaution.
I didnt really get a chance to drive it because It kept on wanting to overheat after I put the radiator back in. so I am letting it sit over night, then I will run the car in teh morning with the rad cap off to bleed out the air.
One last thing. There is a temperature sender on the right side of the radiator with a Plug that goes into it a three pronged one. my actual prong holder broke, so all I have is the three wires, and I dont know which wire goes to the respective prong in the plug, so if someone can take a picture of that for me or make a diagram that would be greatly appreciated as I have had that unplugged.
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I don't know if you will have any luck getting the air out of the cooling system that way. I think you pretty much have to follow the BMW instructions. I won't butcher them by typing them from memory, they are easy to find.
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Ive got a bit of an update for today.
Drove the car around today after bleeding the system the proper way (from the bentley), and to my surprise the problem is almost gone. I think it is more of an ECU issue at this point because I have three ECU's:
mine stock:
Would Drive and pull normal, but for some reason if you downshifted or started cruising at 3.5 RPMs and then punched it it would misfire or hesitate etc. but it would Drive through it completely normal, and would pull through it as well.
mine chipped
same symptoms, except it would be at 4k RPms, and had more difficulty pulling through it. (still pulling a 1244)
Ryans stock: couldnt get problems to arise.
mine Mark D
Ryans Stock
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I found this recently, checking out some unrelated DIY FI stuff:
http://www.diyautotune.com/tech_articles/using_bosch_bip373s_with_megasquirt.htm
Along with this test (http://www.ehow.com/how_7687656_troubleshoot-mosfet-transistor.html), it'll give you a good idea if you have a bad MOSFET coil driver transistor in one or more of your DMEs. I have one with a known bad driver that I'm going to try this test on. Problem is that I don't quite have the tester yet, but I've been wondering what to get for my birthday...so it might as well be that with some nice leads too, eh?
But you swapped the coils, so my whole theory might be nonsense. Since you've pretty much isolated it to the DME, maybe that low impedance coil is overheating the driver & causing some interference when it goes above a certain timing advance? From what I'm thinking...the different chips all set different spark advance curves to maximize power, right? So your overheating DME causes hesitation at different times when it sweeps through a certain range. I know, it sounds far-fetched, but you've tried everything else it seems.
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So should I replace the coils and the dme?
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I'd just get them tested. I'm not sure how to do it yet, but if I tear my spare apart I'll let you know what the procedure looks like.
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I tseted the coils again and kept on getting inconsistent readings for .003 to .007 set on 2k Ohms. every now and then I would get a .002
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I gotta say, you are turning me against going to the COP conversion...
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I gotta say, you are turning me against going to the COP conversion...
the m42 coils are just as bad perhaps. I dont even know if it is the coils.
I think Ive narrowed down the problem of the mid RPM misfire and bucking to be an ECU issue, however, The Cold Start Bogging Is still driving me crazy. I have to wait 15 minutes just for the car to warm up in order to drive it.
(http://dl.dropbox.com/u/11819570/IMG_0063.JPG)
I pulled the plugs and replaced them with some champion plugs. not the best brand, but I dont want to throw money on a second set of plugs when my old NGKS have less than 10K on them.
anyone think the thermostat would cause the problem of cold starting?
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What would cause my two previous ECU's to go bad? and causing me to need a new one?
Still can't figure out the cold start issue:
why would injectors turn off or spark be cut?
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Check out the other thread...I think it's a throttle overrun issue. Maybe the DME thinks you're coasting down a hill and it's killing the injectors momentarily.
I'm also still thinking that the DMEs were damaged by a bad coil pack. I know, I'm like a broken record here... I'd be sure it was that except it's really odd that it changes with the different DMEs. It's not an easy one to isolate.
Did you get the radiator fan stat three-prong fixed? Here's a pic just in case:
(http://i729.photobucket.com/albums/ww299/desktopdave/BMW%20325i/th_IMG_1426.jpg) (http://s729.photobucket.com/albums/ww299/desktopdave/BMW%20325i/?action=view¤t=IMG_1426.jpg)
It's not connected to the DME, just a thermostatic switch that click on the aux fan low or high speed based on coolant temp. Same for the thermostat itself, not related IMHO.
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Thanks a lot dave your a huge help for me in this trouble shooting process. that being said, I ordered two good known working coils off of another member here, so I will switch them out and see if that prevents ECU destruction. I also responded to that thread about hte inejctors switching off.. I am wondering what I should do to tackle it at this point.
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I'm honestly not sure what to do next. You've already done everything I'd do. Hopefully the coils will help with your problem.
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Had a similar issue with a Mercedes, turned out to be a bad afm, running issues were similar plus they were changed by disconnecting the battery which caused a reset of mapping. Your changing ecus may have done same thing.Might also explain onset after timing chain work. Also was not throwing codes for afm on standard diagnostic reader had to get a guy who had actual Mercedes computer.
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We chased a problem like this for a long time. Turned out to be fuel injectors were clogged. The only coil failure we've had is when we rested one on the downpipe from the turbo and almost set the car on fire. It melted that coil but all the others worked great. We've shipped hundreds of these coils and never had a problem.
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We chased a problem like this for a long time. Turned out to be fuel injectors were clogged. The only coil failure we've had is when we rested one on the downpipe from the turbo and almost set the car on fire. It melted that coil but all the others worked great. We've shipped hundreds of these coils and never had a problem.
That's bizarre, why would fuel injectors get clogged only when the engine is cold? I tried swithing out the injectors with four pintle ones, and then back to the old style.
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Our situation was that the car would run okay in the morning, then worse as the day wore on. We chased timing, coils, sensors, fuel pump, ECU, software, grounding straps, spark plugs, fuekl filter, and even thought about sacrificing a chicken.
We then tested the flow rate for the injectors. We removed the fuel rail with the injectors installed, setup each injector into it's own empty and dry water bottle, cranked the engine for 30 seconds, and used a cold medicine dosage cup to measure the results. We had two injectors that were almost non-functional. They would spray enough fuel to let the car idle, and we had tried to tune the problem out by adding more fuel via a longer duty cycle and higher fuel pressure.
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Its backfiring hardthrough the intake and in the exhaust If I leave my goot on the gas while it's boggin.
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crazy idea, most likely not it, still worth a thought and a post at this point. I heard somewhere that a knock sensor might cause issues. maybe some PO changed the engine to a later E36 with the knok sensor and didn't do a good job with the swap.
Another crazy idea: main bearings are toast. too much play could affect the CPS sensor reading and then send false signals to the ECU.
You could check your oil filter for filings (regular proceedure @ every 50h inspections on piston aircraft engine... and those things are realllyyy bullet proof)
just shooting out crazy ideas
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What would I expect to pay if I were to take it to a mechanic?
- should I start throwing brand new parts at it and take it from there?
I mean if it's spitting a camshaft sensor code, maybe thats a good place to start?
Despite the crankshaft sensor reading .560 ohms and the camshaft 1.250 ohms.
thanks.
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Fuck this Motherfucking thing,
So now, After doing 2 70 mile trips, on a good ECU, now it's misfiring again. sometimes It seems to be load dependent others it Seems like its RPM dependant. but it is DEfinitley affected by having my foot on the throttle, and it is acting like it's hitting a limiter or spark cut. The trip was a living hell.
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Lets go a different direction,,, Have you had the alternator tested? I've had single diode failures cause ridiculous problems.
I see you tested the fuel pressure, have you done a long test? Like jump the fuel pump and let it run for minutes? I've had pickup screens clog when run for a while and clear intermittently... Check in fuel tank for water, and other stuff?
Have you tried disconnecting both ends of the battery cable (If you can't inspect the cable) and putting a ohm meter between the cable and ground to check for a weak short.
Pull all the fuses that the car does not need to run. Secondary short could be another cause...
Dave
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I had a tank shrink, it would run fine when full but give the same symptoms youve described when empty, the tank would sag under weight, opening the fuel line, then as it emptied it would pinch the pickup shut.
Dave
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Hey Guys,
Ive just fixed a similar problem myself by adjusting the air idle screw on the MAF, I'm using an e30 m40 MAF on an e36 m42 so for me it was kinda justified, found a fairly good "how to" on bimmerforums for MAF adjustment (i know its for m20/30 but the procedure is the same, and from what I can find so are the voltages)
http://forums.bimmerforums.com/forum/showthread.php?t=1339369
I had really bad starting when hot, unable to accelerate unless ur at WOT for the first 30 seconds or so on start up, then it would clear up and smell really rich of fuel.
now its clean smelling and no pops n farts in the exhaust while sitting at the traffic lights :cool:
I'm aware that this may not be ur problem, but it may be also.....
Just for my 2 cents
P.S. I'm no mechanic just an educated enthusiast.
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Have you checked the fuel tank for sediment?
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The problem seems to be more based upon engine temperature, not necessarily water temp.
Is it possible that a sensor will fail if it is cold?
Im still getting random, occasional missfires at 2,5K- 3k rpm, if I downshift then I can continue driving, and it goes away. maybe it is the same sensor. also, the Tach bounces minimally when it is misfirin.
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My IS is doing the same thing :mad:.... any updates?
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Fifty,
How was the IS running before you replaced the plug wires with COP's? Also I might have missed the posts but I tried to read everything and one of the latest was that you changed the ECU. Did you change the Camshaft sensor? These things are great when they're @ 100% but I tell you what, one little thing goes on with it and BOOM it seems like the whole thing is falling apart.
From a mechanic that you trust you're probably looking at no more than 500 to do everything like that. You're not doing an engine swap or digging deep into the engine. I only have internet currently here at work so I haven't been able to view your video of how it's running but something to consider would be:
Take off the COP's - yes they make them for the E30 M42 BUT... it wasn't stock with the vehicle.
Replace the Camshaft Sensor
Replace the PCV valve
Stupid question but have you checked your plugs? Not the wires, the plugs themselves. They could have had an incorrect one at the MFG and most likely you like pretty much everyone else probably isn't running standard electrode plugs anymore (which really don't lend themselves to adjusting gap). Just a thought. I've been in the middle of an engine swap for the past year (M42 going back in) and it's a pain in the butt how tempermental and touchy these guys are.
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Had similar issue with my M42. Stomp test said cyl #1 had a bad coil. but was actually #3. My advise, buy 1 extra coil and swap-test each one sequentially.
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was looking around on the interwebs and found a tsb dealing with an afm problem. the fix was a chunk of new harness between the old meter connection and the meter. my car had this foot long add in when i got it. not knowing what it was, i removed it and never had an issue....now that i'm having a problem, well i can't find the chunk of harness.
Fifty, do you have this add-in in your harness?
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Was this ever solved fully?
My IS is doing some odd things like this.
This weekend I plan on cleaning up the ICV and looking to replace the vacuum leaks.
Could this haven anything to do with my MPG gauge not working right? It uses vacuum I think.
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Ignition problems are troublesome to track down. We found one that had a bad coil AND a bad DME. The coil drivers tend to be killed when the coils die. Rob's COP kit is a great solution to the problem...I have one and will heartily recommend it.
MPG gauge is just a calculator. It uses the injector bandwidth divided by MPH to get your instant MPG.
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Ignition problems are troublesome to track down. We found one that had a bad coil AND a bad DME. The coil drivers tend to be killed when the coils die. Rob's COP kit is a great solution to the problem...I have one and will heartily recommend it.
MPG gauge is just a calculator. It uses the injector bandwidth divided by MPH to get your instant MPG.
The mpg gauges is either at zero mpg when I give it any gas at all or 40 mpg when I let off. There is no in between.
This weekend I want to do a tune up (plugs, wires, air and fuel filter) and I want to redo the vacuum hoses and clean the icv
Little back round on the symptoms, seems like mine didn't have any issues when it is cold. But once the car is warmed up and I stop at a couple lights, the idle begins to flutter and I get this miss/stutter under acceleration. The miss seems to go right with my gas pedal input.
I probably should make my own thread.
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I had the same problem with my gauge when the diff speed sensor was flaking out. But the speedo would also hesitate as it swept across the gauge face.
Did you check the coolant temp sensor or the air temp sensor? Might be the O2 as well. I think what's going on is that once the car is warmed up, one of those senors is still reporting full cold; the injection keeps it rich, and you get spark plug misfires. Alternatively, the O2 isn't reporting the right exhaust mix. If the problem goes away at WOT, it's likely not the O2 sensor though.
A cheap test is to look at the plugs and see if they're black & sooty with fuel deposits.
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I just read this entire thread hoping to find an answer to this nagging bucking misfire issue. I think I'm one of four or five people on here that have had or are having this problem.