Author Topic: I need some Serious $#%@#$in Help seriously (Read 26632 times)

fiftytakedowns · « **Reply #30 on:** February 14, 2011, 04:40:13 PM »

They are VERY VERY VERY lean

the shop has smoke tester I'll try

B318M42W · « **Reply #31 on:** February 14, 2011, 05:21:05 PM »

all plugs are like that? just #1? or #1 and #3

IIRC, cyl injectors 1&3 are linked

fiftytakedowns · « **Reply #32 on:** February 14, 2011, 05:23:54 PM »

I'll pull the plugs this friday and see what I get

fiftytakedowns · « **Reply #33 on:** February 14, 2011, 07:39:31 PM »

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?

colin86325 · « **Reply #34 on:** February 15, 2011, 10:13:29 AM »

Yes, relays can sometimes cut out. If those are your original 20-yo reays you should replace them as preventative maintenance.

fiftytakedowns · « **Reply #35 on:** February 16, 2011, 02:32:09 AM »

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.

silverm3bmw · « **Reply #36 on:** February 16, 2011, 08:32:03 AM »

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??

fiftytakedowns · « **Reply #37 on:** February 17, 2011, 02:28:12 AM »

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?

longtallsally · « **Reply #38 on:** February 17, 2011, 05:03:58 AM »

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...

fiftytakedowns · « **Reply #39 on:** February 17, 2011, 05:40:18 PM »

Quote from: longtallsally;101584

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.

silverm3bmw · « **Reply #40 on:** February 17, 2011, 07:25:46 PM »

Did you even verify with a pressure gauge it was losing fuel pressure?

fiftytakedowns · « **Reply #41 on:** February 18, 2011, 01:53:31 AM »

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.

Quote from: silverm3bmw;101601

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.

fiftytakedowns · « **Reply #42 on:** February 18, 2011, 01:56:30 AM »

double post

longtallsally · « **Reply #43 on:** February 18, 2011, 07:56:07 AM »

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.

fiftytakedowns · « **Reply #44 on:** February 18, 2011, 11:24:35 PM »

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?