M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: Burnall4 on January 21, 2009, 01:02:57 PM
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Sorry to start a new thread but I have been gone for so long. I was trying to dig through the old threads but I was unsuccessful in my attempts to find a definitive answer.
Did we ever figure out why we have the Hot Start Problem. I have my car back now and I am about to do some work on it, so I was wondering, before I just jump in the engine like a vrigin on prom night; did we in fact find what cause the car to shake violently, stutter, have no ability to accelerate etc...after the engine was hot?
Thanks
Gray
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Nope, sorry Gray. I was hoping the fuse box thing would be the answer, but haven't heard anything since... let us know if you find anything.
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well in that case, here goes nothing....wish me luck I am going to start systematically rebuilding the engine...I will make a new thread and update when I actually start
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I do wish you luck... unfortunately I don't believe this problem has anything at all to do with the engine. It's going to be some other system or sensor I think. My motor did not do this in the last car it was in and has done it since the swap. My original motor did this as well, and has since been installed in another vehicle and has no issues.
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I believe it will have something to do with the wiring harness between the engine ECU and engine sensors. Possibly some sort of continuity, earth problem etc.
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Well I know what fixed mine and it will only help you if you hooked the mystery wire up like I did. I disconnected it and all is well.
Lower left corner of this graphic.
(http://img218.imageshack.us/img218/6942/0188ed8.jpg)
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Holy crap... that actually has a chance at being it. I think I remember hooking that wire up after the swap. Will take a look today. Thanks for posting that.
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UPDATE: I OWE YOU A CASE OF BEER OR SOMETHING!!!
As soon as I disconnected that wire I took the car for a drive to get it nice and warmed up. Shut if off and waited 5 minutes. It started back up perfectly with no hesitation or stalling. I've started it 4 times since and had no problems. It fixed it IMMEDIATELY and completely with no reset of the ECU or anything.
I can not tell you how frustrating this problem has been... LOL it feels like a brand new car now that I don't have to deal with letting it idle for 2 minutes before trying to drive it. Thank you again!
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WHAT WHAT WHAT ACSHNITZ! please tell me which whire it is!
FOUND IT!!!!!!!!
UNPLUGGED IT!!!!!!!
GOT THE CAR WARM AT IDLE (In my parking deck still at work)
Cut it off, turned it back on (i can get it to replicate the problem like this) and WOOOOOOHOOOOOO nothing, no hesitation, no anything just glass idle and accelration!!!!!
UPDATE! So far so good, have tested it out for the past hour doing some errands and not the first sign of any of my past problems!
if this is IT, like the fix! I will have to hook you up with something kind sir!!!!
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Could someone be a little more clear about this? Perhaps circle the wire you are talking about in paint plz :)
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i guess it is finally solved..
props to sports.racer
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I am currently packaging my first-born male son. Please provide shipping address so that I may send him to you.:)
I disconnected the wire from my car this morning and have started and stopped the car 6-8 times during the day.
The hot start rough running condition is definitely fixed!
I resurrected this car from the dead in October. (It had been sitting in a barn for 6 years with the engine out and disassembled.) During the reassembly, I specifically remember seeing the subject connector and wondering what it was for. I plugged it in, blindly, along with the other zillion disconnected wires.
I guess I shouldn't have connected this one. :confused:
To help those that don't know where this wire is: It is in the engine compartment, on the firewall, right in the center of the car. You have to remove the large plastic cover that covers all of the wires. If you remove this plastic panel and don't see a loose connector/wire, you have found the problem.
Thanks again Sports.racer. I would have never figured this out without your help.
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(http://lh3.ggpht.com/_b8Z4JG2u6eo/SX-rHkG9B5I/AAAAAAAAAkw/mpjrcgK8zy4/s640/0188ed8.jpg)
So basically you look at the wire thats outside of the taped wires? I will have to check this out when i get home. I did basic paint to attempt to make it a lil more clear...
STICKY PLZ?
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EN318is, you got it that is the one!
WE need to make .racer the hero of the board :D
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You have the correct location.
If you see two wires that are unplugged, that's the way it should be and you haven't found the cause of any problem.
If you don't see any disconnected wires, find the black wire with the white stripe and disconnect it at the connector.
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Amazing guys... And yes .racer gets my vote for hero of the board.
Glad we will all have properly running m42's again.
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How many more people have fixed their problem with this fix?
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How many more people have fixed their problem with this fix?
I know I have, now I just need replace the worn out hoses in the engine so I can stop having those tiny vaccum leaks, and I need to eventually replace the AFM, but for right now the car is running like a champ and thats all I care about :D
Side note: talked to my mechanic this morning and he was like wow!
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Mine was plugged in and it was pretty obvious which wire it was!!! My car is currently in pieces so I cannot for sure say it fixed mine but im 99% sure!!!
+1 vote Racer for MVP of M42!!
Where did you find that image? I am curious what other goodies are the previous pages!
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Very cool. I never knew this feature existed.
BTW, where is the idle speed CO potentiometer located?
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Very cool. I never knew this feature existed.
BTW, where is the idle speed CO potentiometer located?
It sits on top of the air flow sensor. Pages 13-52 and 53 of the referenced manual.
http://www.m42club.com/forums/showthread.php?t=964
Now I understand how my car runs without an O2 sensor:o
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I had this same problem! However I just took the casing off that part of the wiring harness when I was trying to get at the blower motor and saw that those two wires were disconnected....so I connected them...put everything back together and got shitty idle for a long time and engine cut offs. Until I remembered I had attached that wire, I unattached it and everything went back to normal, never figured out what it was though...until now...I am still kind of unclear though....what exactly does it mean when it is plugged in? It says that is for when the Catalytic converter is not installed? That doesn't make sense to me, because I have no Cat on my exhaust, and it still runs like shit with it in....anyone care to explain it to me in simple minded terms? =P
anywho....I'm leaving that wire disconnected. ^__^
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I had this same problem! However I just took the casing off that part of the wiring harness when I was trying to get at the blower motor and saw that those two wires were disconnected....so I connected them...put everything back together and got shitty idle for a long time and engine cut offs. Until I remembered I had attached that wire, I unattached it and everything went back to normal, never figured out what it was though...until now...I am still kind of unclear though....what exactly does it mean when it is plugged in? It says that is for when the Catalytic converter is not installed? That doesn't make sense to me, because I have no Cat on my exhaust, and it still runs like shit with it in....anyone care to explain it to me in simple minded terms? =P
anywho....I'm leaving that wire disconnected. ^__^
I detect a hint of female in this post...am i correct?!?!
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Congratulations guys and gals on fixing your problem. Sports.racer great job.
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Well I'm just glad my car is running well again and that I was able to help so many people get their cars running well again. I've certainly received enough help and good ideas here.
What a silly thing this was, I have a thing about disconnected wires and just hooked it up when I saw it disconnected without further thought.
Took a while to notice the hot start problem, it seemed to just get worse and worse, it wasn't a sudden change. Did anyone else notice that it took awhile to get bad or is it just my imagination.
Anyway, it appears to be fixed and I'm putting tape over those connectors so I won't have another brain cramp and hook them up again!
Happy stumble free driving everyone!
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Wow. Good work sports racer. I don't have this problem but have been following other peoples search. Hard to believe it was something so random. Well done.
+1 to sticky this, or move it into a list of common problems/fixes where it will be easy to find.
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Fixed. When I saw the solution post Thursday night, it was 2am and raining, but I grabbed a flashlight and ran out in the rain to try it. This infuriating problem has been driving me insane and keeping me from liking this car. Thank You!
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Before I do this today, what is the point of this wire and what is it telling the car differently then it was before. I will be the happiest dude alive if I could fix this problem. Just let me know what this wire does first.
And by the way, under your signature, you can now say
idle problem 1 billion, me 1
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i detect a hint of female in this post...am i correct?!?!
+1
!?!?
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Sports.Racer.... Do you like beer???
Cuz I swear if I wasn't seventeen I would buy you a whole liquor store!!!!! I can not believe that has fixed the problem...
Please sticky this for anyone who has this problem!!!!!!!!
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Wow, I had no idea the hot start issue was such a big deal. Surely the cars didn't do this from the factory, so what has changed in all of your cars to cause bad driveablility on a hot start? I'm still plugged in and I have no issues whatsoever...
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Gearhead E30:
I wonder if that black/white wire is disconnected somewhere else on your car. It sure made a difference on mine.
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Their cars had been worked on and whoever reconnected the wire?
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My guess would be that the wire "option" is for:
1) connected wire = Euro M42's (or M42's that are overseas which did not have the catalytic converter)
2) disconnected wire = US M42's (or M42's which are Stateside and MUST have a catalytic converter)
I'm also wondering if the Euro M42 DME is different, or more so, if it operates w/ different parameters and that is why the wire HAS to be connected on the other side of the pond....
I'm sure for those M42's on this side of the pond, with the wire needing to be disconnected, that the DME must operate most efficiently and properly based on that "disconnect" - and if that specific wire is erroneously connected, the DME then has to run in some sort of loop (or is it open loop) mode to keep the car running, maybe not as efficiently, but enough so that it does not stall or leave the driver completely stranded.
I'll have to check this wire on mine too, because I have no idea if it is connected or disconnected... (and how many M42 owners actually know about this wire or have ever even had the black plastic covering off of the main firewall harnesses)....
Just out of pure curiousity, for those that have "fixed" their M42's after disconnecting the wire, did any of you notice poor gas mileage or poor engine efficiency prior to finding the fix?
GREAT FIND - this NEEDS to be made into a STICKY for sure!
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Thanks!!!!!!!!!
This really solved my warm start problem to.
Installed this engine in my bmw E21 last year and have had problems ever since. Never would have guest this little connector coused all the problems.
Thanks again!
:):):):):):):)
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My guess would be that the wire "option" is for:
1) connected wire = Euro M42's (or M42's that are overseas which did not have the catalytic converter)
I'm also wondering if the Euro M42 DME is different, or more so, if it operates w/ different parameters and that is why the wire HAS to be connected on the other side of the pond....
I have a Snap-On MT2500 scanner and printed out my ECU (aka DME?) info:
ECU Type: M1.7
ECU hardware: 0261200175
ECU software: 1267356214
BMW hardware: 1727900
BMW software: 001
Product: 949
SID: 0005
My vehicle is a non-cat version and when the receptacle is disconnected the idle goes to crap. When I set the scanner up for the "cat version" and look at the engine data, reference voltage for the O2 sensor is present.
It appears to me the ECU is set up for both cat and non-cat applications and the connector is sort of a "switch" if you will. EDIT: The eprom is actually the "switch" so to speak. US Spec #1.267.356.378; Euro-spec #1.267.356.214
-If connected the DME looks for an input signal from the Idle Speed CO Pontentiometer, but it must have the Euro-spec eprom #214.
-If disconnected the DME looks for input signal from the Oxygen Sensor, but that is for US spec eprom #378.
The DME (aka ECU) part number on the case is the same for both US and Euro markets (0261200175).
Wish I could find something in the wiring manual, but there's nothing that jumps out at me and I'm not all that good with schematics anyway:o
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Yes! It worked for me too! TYVM!!!!
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I have a Snap-On MT2500 scanner and printed out my ECU (aka DME?) info:
ECU Type: M1.7
ECU hardware: 0261200175
ECU software: 1267356214
BMW hardware: 1727900
BMW software: 001
Product: 949
SID: 0005
My vehicle is a non-cat version and when the receptacle is disconnected the idle goes to crap. When I set the scanner up for the "cat version" and look at the engine data, reference voltage for the O2 sensor is present.
It appears to me the ECU is set up for both cat and non-cat applications and the connector is sort of a "switch" if you will.
-If connected the DME looks for an input signal from the Idle Speed CO Pontentiometer.
-If disconnected the DME looks for input signal from the Oxygen Sensor.
Wish I could find something in the wiring manual, but there's nothing that jumps out at me and I'm not all that good with schematics anyway:o
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Interesting info!
When you pull your DME out, can you tell us what the numbers are on all or any exterior labels you see?
On an M42 DME here in the US, the Motronic label on it usually has this part number on it: 0 261 200 175. These DME's are commonly referred to and known as the "175" in the used M42 market or online forums - so when someone is in need of a replacement DME for a US M42, the DME is a "175".
I'm just curious if your DME is different from a US spec vehicle that has the catalytic system over a Euro which does not.
For an example, here is a good reference of a 91 M42 US spec DME (thanks to M42 Member rallyegolf for posting the pics in his classified ad on here):
http://www.m42club.com/forums/showthread.php?t=7884
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The factory repair manual mentions something about "catalytic converter protection" and how the mixture is enriched slightly to prevent overheating the element.
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Wow, does the E36 M42 have a Run Like Crap wire?
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Interesting info!
When you pull your DME out, can you tell us what the numbers are on all or any exterior labels you see?
On an M42 DME here in the US, the Motronic label on it usually has this part number on it: 0 261 200 175. These DME's are commonly referred to and known as the "175" in the used M42 market or online forums - so when someone is in need of a replacement DME for a US M42, the DME is a "175".
I'm just curious if your DME is different from a US spec vehicle that has the catalytic system over a Euro which does not.
For an example, here is a good reference of a 91 M42 US spec DME (thanks to M42 Member rallyegolf for posting the pics in his classified ad on here):
http://www.m42club.com/forums/showthread.php?t=7884
Same number on mine as in rallyegolf's pic: 0 261 200 175. The number of the installed chip is 1267356214.
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I finally got around to doing this the other day. I can't believe that it was something so smiple to fix. thanks sports racer, you the man
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sticky this now
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Wish I could find something in the wiring manual, but there's nothing that jumps out at me and I'm not all that good with schematics anyway:o
In terms of wiring diagrams see here, using the grid reference look at E6...
The wire comes from the air flow meter to an input on the ECU called LLCO ( maybe Light Load CO2 but thats a complete guess). and shows as "not connected w/catalytic convertor"
http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/fig02.pdf
There are wiring diagrams for nearly everything here
http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/
I'm retro fitting an o2 sensor to my car (euro non cat) to use with the LPG kit I am installing, once it's in I'll hook it up and see if I get the same problems, euro ECU's are supposed not to work with the O2 sensor hooked up as they need different software, but it may be all to do with this connection.
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In terms of wiring diagrams see here, using the grid reference look at E6...
The wire comes from the air flow meter to an input on the ECU called LLCO ( maybe Light Load CO2 but thats a complete guess). and shows as "not connected w/catalytic convertor"
http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/fig02.pdf (http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/fig02.pdf)
There are wiring diagrams for nearly everything here
http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/ (http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/)
I'm retro fitting an o2 sensor to my car (euro non cat) to use with the LPG kit I am installing, once it's in I'll hook it up and see if I get the same problems, euro ECU's are supposed not to work with the O2 sensor hooked up as they need different software, but it may be all to do with this connection.
That's why I love these forums! I ran back through the other wiring manual (http://www.theguestroom.net/m42/e30_91_modified_re.pdf) and see it on page 1360-4 as well.
Thanks for the info and I'll be waiting to see what you come up with when the conversion is complete.
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just an interesting note: my car doesn't even have the mystery plug, and the harness is original so it wasn't removed. Build date 3/90 fwiw
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I'm also in for a sticky... this problem plagued TONS of ppl and it should be easily found by any new sufferers who just bought their 318is and are wondering why it does this.
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This thing hasn't been stickied yet?!? Hmmm maybe I should just delete my original post :P
Anyway, I have been driving my car for a while now and everything is great, except I figured out my AFM is crapping out. So, I guess I got to replace that. On another positive note, my gas mileage has increased, not leaps and bounds but it has. I was getting 290 to a full tank in the city, now I am getting 310-320. Anway. Now I just have to do some routine maintanence and out this car to work, ehehehe!
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To answer the question, I have acttually gotten about the same gas mileage... No problems or decreases whatsoever... Also, does thisbplig have to do something with the air fuel mixture on startup?? Because I had a fuel problem with the plug connected and now there is no black smoke on startup!!!
Secondly, I have found that with this disconnected wire... The car absolutely kicks the ass of modern bmw's with a bottle of Lucas oil octane booster and sunoco 93 pump gas!!! It's a little too fast... Secondly it pulls really good at low rpms... An yes I know it is bad for the clutch... There is no need to downshift as the car pulls like otbis a gear lower than what it really is!!!
Whooo!!!
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Still going smooth. This thread is the best thread evar.
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Wow, my problem is finally solved.
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Tthe other wiring manual (e30_91_modified_re_(2)) and see it on page 1360-4 as well.
Never mind, found the manual...
Nice stuff on that site you posted, thanks.
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I was getting 290 to a full tank in the city, now I am getting 310-320. Anway.
Really? I'm lucky to get 250, I don't think my right foot is that heavy. What kind of range are others getting?
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I just got 330 with mixed city driving... worked out to just over 27mpg. This is after the "fix." Before disconnecting that wire I was getting 24-25mpg mixed city.
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I think this has improved my gas milage also. Before i was getting around 290 mixed city/hwy. But my last full tank i got 315mi on mostly city. :)
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Wow, my mileage is pretty low compared to yours. Maybe I need a new o2 sensor to start with, I'm sure it's never been replaced.
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I get an average of 27 according to both my calculations and the OBC, and I don't have a plug. Were you guys' plugs just hanging out of the harness or did you have to unwrap it?
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I got 21.5 on my last tank - going to have to fix this.
The evil wire in my car was fully exposed on top of the bundle. It looked like I had accidently pulled them which is why reconnectd them.
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I get an average of 27 according to both my calculations and the OBC, and I don't have a plug. Were you guys' plugs just hanging out of the harness or did you have to unwrap it?
Yea, mine was just right there out in the open.
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I get upto 330 from a tank, mostly motorway miles, 2 runs a day to and from work ~18miles each way, so 2 cold starts a day, cruising at an indicated 85mph, but actually at 3800-3900rpm, so ~78-80mph in reality.
In US gallons (3.78litres) that's 27-28mpg (I think), in UK gallons (4.54litres) that's 33mpg.
I didn't have a lambda sensor as euro cars are non-cat versions, but I am converting to run on lpg so I've had 2 lambda bosses welded in, since then I've hooked up a new factory sensor and un-plugged the cable, it took about 3-4days to settle down (lumpy idle) with the sensor connected but now it pulls much better on part throttle, particularly at motorway speeds.
Also we run on minimum 95ron fuel in the UK and can get 97-98ron at every filling station so the tuning on the original ECU is setup for this which may help economy. The ECU is tuned for 95ron, so running 98 makes little difference to a car this age.
I haven't used a whole tank of fuel yet so I don't know if the fuel economy has increased, it looks like it may have done as the tank doesn't seem to be emptying itself as fast, but that may be wishful thinking...
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Thanks for sorting it out. Finally I got my problem resolved. And got through the emission test last weekend.
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This thread is full of win........epic win
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Will try this today!
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I have been frusterated by my HOT idle ever since I bought it. Thank you so much your my hero too;)
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What surprises me is how many people are having this problem. Interesting. Glad the fix is so easy though!
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Will try this today!
it DID fixed it :cool::cool:
thanks man!
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Luckily, this has never been a problem in my "IS." HOWEVER, My 85 318i with the ever solid M10 engine is doing this. I wonder if this same fix will work for that too.....
im trying this nright n ow onmy 318i....i cnt find a black and white striped wire.....found a green one.....tried unplugging....nothing changed. i felt aroundon the main group of cables and it feels like there is a plug in there....
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Wow, I don't want to jump the gun and jinx myself, but I think it fixed my baby too! Thank you speed.racer! I too think the idle was becoming rougher with time, which is why I thought I'd check back in with this forum and see if there have been any new leads before I dumped more money on sensors.
I also agree the the throttle response seems much better in low rpms. I'm falling in love with this car all over again!
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Makes me wish mine was plugged in, so I could go and unplug it! Mine is taped safely apart on the outside of the harness.
I get low 20s in the city. I'm taking it out for a long trip this week, I'll report back on fuel mileage.
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I edited my post to include the part number information between the US and Euro DME EPROM.
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My car is running like absolute crap, with or without the wire :(. It's running VERY rich and it stalls very, very frequently. Since I've had the car (approx 40k miles) I've replaced the ICV, the camshaft position sensor, cleaned the throttle body, put fuel injector cleaner in, the works!
I really need your help guys, this is my only means of transportation :( Thanks!
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Can this be done od the E36 M42?
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Can this be done od the E36 M42?
please someone??:(
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I don't know about the e36...but they're practically the same car. Can you find anything like that plug on the wire harness going across the firewall? Our e30s have them taped on the outside, just begging to be plugged in.
My car is running like absolute crap, with or without the wire :(. It's running VERY rich and it stalls very, very frequently. Since I've had the car (approx 40k miles) I've replaced the ICV, the camshaft position sensor, cleaned the throttle body, put fuel injector cleaner in, the works!
Here's a few quick tests that won't take much time...do the stomp test...post your findings here. I'd check the throttle position sensor, the coolant temp sensor, the AFM air temp sensor & flap resistance. How old is your O2 sensor? Not to snipe, but if you think cleaning the throttle body is the works...you'll have so much fun learning on this car...:p
I forgot to add my mileage figures from my earlier post...I get low 20s around town and I've hit 35 highway. That's 42mpg Imperial, 6.7 L/100km (I can brag in metric too).:D
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Here's a few quick tests that won't take much time...do the stomp test...post your findings here. I'd check the throttle position sensor, the coolant temp sensor, the AFM air temp sensor & flap resistance. How old is your O2 sensor? Not to snipe, but if you think cleaning the throttle body is the works...you'll have so much fun learning on this car...:p
Thanks for all of the suggestions. I left out a few details because I was in a bit of a hurry trying to get my car back together!
-Stomp test gave me the incredibly helpful lambda code (1222)
-Throttle position sensor was replaced in January, 2k miles ago.
-Where is the coolant temp sensor and the AFM temp sensor?
-o2 sensor is a year old.
-I know, I have no problem pulling things apart on my car, but there's only so much I can do down at school, away from my garage! :p I threw in new plugs, threw in some Techron in the gas tank and used a zip tie on the throttle cable to raise the idle by 300 rpm and the car drove well enough to make it home! Now I've got the intakes off and I'm replacing all of the vacuum lines.
Hopefully this will sort out my idle issue, but I'm not sure about my A/F ratio. Whenever it comes back together I'm going to test my fuel pressure, and while I'm waiting for gaskets to arrive I'm going to check the coil resistance. Any other suggestions?
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I cut wire in pin 14 blacck with white stripes
tomorrow I will take a picture
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Thanks for all of the suggestions. I left out a few details because I was in a bit of a hurry trying to get my car back together!
-Stomp test gave me the incredibly helpful lambda code (1222)
-Throttle position sensor was replaced in January, 2k miles ago.
-Where is the coolant temp sensor and the AFM temp sensor?
-o2 sensor is a year old.
-I know, I have no problem pulling things apart on my car, but there's only so much I can do down at school, away from my garage! :p I threw in new plugs, threw in some Techron in the gas tank and used a zip tie on the throttle cable to raise the idle by 300 rpm and the car drove well enough to make it home! Now I've got the intakes off and I'm replacing all of the vacuum lines.
Hopefully this will sort out my idle issue, but I'm not sure about my A/F ratio. Whenever it comes back together I'm going to test my fuel pressure, and while I'm waiting for gaskets to arrive I'm going to check the coil resistance. Any other suggestions?
I would bet that it's either your coolant temp sensor or your fuel pressure regulator (FPR). When either of these items fails, usually your car will run very rich. Sometimes you can smell gasoline in the vacuum hose of a bad FPR.
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(http://i228.photobucket.com/albums/ee60/bane0403/Zica1-1.jpg)
I cut black wire with white stripe pin 14
is that ok?
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(http://i228.photobucket.com/albums/ee60/bane0403/Zica1-1.jpg)
I cut black wire with white stripe pin 14
is that ok?
Why are you cutting this wire?
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(http://i228.photobucket.com/albums/ee60/bane0403/Zica2.jpg)
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Intake temp sensor is mounted inside the AFM. You'll have to pull the connector and do a voltage test I think. It's in the Bentley.
I think the blue 2-prong connector is the right one...the DME coolant temp sensor. I'd test it anyway.
Testing the O2 sensor is easy...disconnect it and see if the hot start problem gets worse/stays the same. If not, suspect it as bad...even if it's been replaced recently.
I have no idea what the wire cutting is about either...please clarify...
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really do not know
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really do not know
That makes at least three of us that don't know. :confused:
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I was looking for black and white wire and that is the only one I could find
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I was looking for black and white wire and that is the only one I could find
Ok, put a splice in that wire you cut.
The wire we're talking about is in circled in this drawing.
(http://lh3.ggpht.com/_b8Z4JG2u6eo/SX-rHkG9B5I/AAAAAAAAAkw/mpjrcgK8zy4/s640/0188ed8.jpg)
No cutting required, the wire has simple push connectors.
In your case, I'm guessing you don't have a catalytic converter and the wire should be connected.
If you do have a catalytic converter, then disconnect the wire.
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i didn't find that connetor
I drive e36
may not be the same as at e30
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Yeah, they tidied up the wiring in the e36, so no plug for you!
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:(
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To the OP, if you arent drunk enough already, consider me owing you a beer or 2 myself. Been dealing with this for as long as ive had the car and assumed it was a vacuum leak. And add a beer to desktopdave as well for pointing me to this thread.
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:D
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This was awesome!
Mine was not a hot start issue. My car would nearly die out after starting it and trying to just take off without letting the car idle for a couple of minutes.
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I'm gonna have to check that. SInce I installed my chip the car has been running like shit at idle, I wonder if I didn't plug this back by mistake. My car comes from germany and they had cat converters there :(
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Ugh, I have all of the problems found in this thread, except my wire is unplugged. The engine only runs badly when it's warm-ish (the needle on the temp gauge is just past the blue mark). When it's cold from sitting all night, or once it's nice and warmed up, it runs just fine. What could this be? It's driving me insane!
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I have a tiny bit of tach needle-wandering and a very, very mild stutter when I first start mine up. I'm def. going to check this plug out once I get the intake back on and such from cleaning up the acid trip cooling/vac/hc hoses from under there.
Systema - ICV perhaps? Ever changed or checked your plugs/wires? Any other symptoms you can narrow down?
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Systema - ICV perhaps? Ever changed or checked your plugs/wires? Any other symptoms you can narrow down?
New plugs, not sure about the wires but they look pretty new. The old plugs were pretty carbon-y, and I know the car's running kinda rich. I can't tell for sure, but it smells like there's gas in the oil. That's probably a bad sign, huh?
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I'm wondering if our E36s have something similar, but it's integrated into one of those multi-wire plugs. Kinda like how we have to do some funky splicing to install a COP kit. I can't find anything like this in the wiring diagrams, though.
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I've been fighting this bump and sputter problem forever. If this wire thing fixes this very frustrating problem I'll be one happy camper.
By the way I'm new on the block. I have two BMW's, a 87 325 and a 91 318, both rag tops. I love um.
It's great knowing that this site is out there. Thanks
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I have to do this
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Why doesnt it change Anything on my car?
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does it suits e36 318is with m42?
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For e36 318is owners with m42 engine,check this thread from bmw club Malaysia
http://www.bmwclubmalaysia.com/forums/showthread.php?t=29895
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Just wanted to add that this fixed my problem as well. Connected the wires after I accessed the blower fan and forgot what I did once I noticed the problem. Car would sputter/stall after a start when warm unless I either let it idle for a couple minutes or stomp on the gas for a few seconds until power returned.
Read this thread last night and disconnected it. Been running smooth since.
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Another success story reporting in! This was such a frustrating problem, glad a fix has been found.
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Where should I search for the cable in 93' E36 M42 Coupe? Does it have it? I read the thread from BMW club Malaysia and I've tryed with the Fuel regulator from my old engine and there is no difference with it.
The problem is that when I turn off the car for example for 5 to 8 minutes. When I start it ,she runs like she's out off fuel and if I let go the gas pedal and she turns off.Then 1 minute she is trying to start with no sign of life and then it starts and working the same(like no fuel) way 2-3 minute.After that the engine runs perfect with perfect idle.
I've tryed with other: TPS ,air flow meter, temperature senzor(water-it was broken)Idle speed sensor and other things.
The engine is not the original one on the car. This engine is from a 92 IS coupe . Are they any differences between 92 and 93 ECU ?
Becouse i run the car with the ECU from the original engine?
edit: Sorry about my english..!
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Where should I search for the cable in 93' E36 M42 Coupe? Does it have it? I read the thread from BMW club Malaysia and I've tryed with the Fuel regulator from my old engine and there is no difference with it.
The problem is that when I turn off the car for example for 5 to 8 minutes. When I start it ,she runs like she's out off fuel and if I let go the gas pedal and she turns off.Then 1 minute she is trying to start with no sign of life and then it starts and working the same(like no fuel) way 2-3 minute.After that the engine runs perfect with perfect idle.
I've tryed with other: TPS ,air flow meter, temperature senzor(water-it was broken)Idle speed sensor and other things.
The engine is not the original one on the car. This engine is from a 92 IS coupe . Are they any differences between 92 and 93 ECU ?
Becouse i run the car with the ECU from the original engine?
edit: Sorry about my english..!
Anyone ?
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Where should I search for the cable in 93' E36 M42 Coupe? Does it have it? I read the thread from BMW club Malaysia and I've tryed with the Fuel regulator from my old engine and there is no difference with it.
The problem is that when I turn off the car for example for 5 to 8 minutes. When I start it ,she runs like she's out off fuel and if I let go the gas pedal and she turns off.Then 1 minute she is trying to start with no sign of life and then it starts and working the same(like no fuel) way 2-3 minute.After that the engine runs perfect with perfect idle.
I've tryed with other: TPS ,air flow meter, temperature senzor(water-it was broken)Idle speed sensor and other things.
The engine is not the original one on the car. This engine is from a 92 IS coupe . Are they any differences between 92 and 93 ECU ?
Becouse i run the car with the ECU from the original engine?
edit: Sorry about my english..!
sorry double post
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sorry double post
Problem solved,
The car Has a LPG system, the problem was a gas valve.
The other problems was a water temperature sensor - the blue one on the cyl. head.
:)
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hello everybody, i've been dealing with this no start issue for awhile now. i just wanted to find out if anybody has some suggestions so here goes. Here's a list and current condition of my m42 in my E30 318is.
Replaced (in total)
- o2 sensor
- took care of mess under intake manifold
- changed sparkplugs
- replaced air filter with a K&N drop in
- swapped out ICV (no change with cleaned original and replacement)
- throttle body (no change with cleaned original and replacement)
- put in injector cleaner
- put in a new fuel pump
- put in a new fuel filter
- replaced fan clutch
- replaced thermostat and gasket
- replaced timing chain tensioner
the car starts after long periods of time being off.
like over night. or sometimes after 20~30 mins after being started and turned off. i had a problem before with sporadic idling where as my icv would cause 2k-3k of idling. what i've noticed is that the car is getting flooded with fuel. you could smell fuel and after those periods of rough starts white smoke will come out of the exhaust smelling of fuel. another note is when i got the car, it had no cat converter. idk really if it has anything to do with this but i figured i'd mention.
what i've been doing lately is opening the airbox, and then close it back. out of all the times i've done this, the car would start with the help of the gas pedal being stepped on. usually halfway open throttle body.
i have done no tests whatsoever with the sensors and such though. haven't gotten around to getting a voltemeter and learning how to use one. lol
any input would be appreciated.
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either a replacement dme or it was because i cleaned up my CPS which was so gunked up with what i believe was power steering fluid running from the reservoir and somehow got there. :confused:
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I've only had my 318i running for a week or so and noticed this issue....same as everyone has described, it would start right up when cold but after it was warmed up it would require me to hold my foot on the gas pedal to keep it running but after a few minutes it would run fine. I found that the little wire was connected....and I just disconnected it. This did help the idling, but I still have to use a little bit of gas pedal to get it to start right away. So I'd say this is another success story, thanks for posting this information!
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Hey everyone,
New to the forum and picked up a '91 318is a couple of weeks ago. Been busy finishing school but this hot start problem has been bugging me ever since I got it. Previous owner swapped DME's, replaced O2, as well as several other components until him and his mechanic got stumped. He just did the old stomp trick to get by and advised me to do as well but I figured I'd try to get to the bottom of it.
I was suspecting TPS or AFM but stumbled across this thread and man, what a great fix! Best fixes are free ones like these! Wire was plugged in on my car too and yes the problem has gone away also. Thanks again Racer
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hello everybody, i've been dealing with this no start issue for awhile now. i just wanted to find out if anybody has some suggestions so here goes. Here's a list and current condition of my m42 in my E30 318is.
Replaced (in total)
- o2 sensor
- took care of mess under intake manifold
- changed sparkplugs
- replaced air filter with a K&N drop in
- swapped out ICV (no change with cleaned original and replacement)
- throttle body (no change with cleaned original and replacement)
- put in injector cleaner
- put in a new fuel pump
- put in a new fuel filter
- replaced fan clutch
- replaced thermostat and gasket
- replaced timing chain tensioner
the car starts after long periods of time being off.
like over night. or sometimes after 20~30 mins after being started and turned off. i had a problem before with sporadic idling where as my icv would cause 2k-3k of idling. what i've noticed is that the car is getting flooded with fuel. you could smell fuel and after those periods of rough starts white smoke will come out of the exhaust smelling of fuel. another note is when i got the car, it had no cat converter. idk really if it has anything to do with this but i figured i'd mention.
what i've been doing lately is opening the airbox, and then close it back. out of all the times i've done this, the car would start with the help of the gas pedal being stepped on. usually halfway open throttle body.
i have done no tests whatsoever with the sensors and such though. haven't gotten around to getting a voltemeter and learning how to use one. lol
any input would be appreciated.
Glad you solved your problem...but I read this & had to chime in...get a multimeter & start testing. You'll save a ton of time, money and frustration. Even a $4 HF cheapie is better than nothing.
Grab the e30 electrical troubleshooting manuals (ETM) too.
Mine had the same problem when I got it...the cam PS and cam cover gasket was leaking enough oil to cover the CPS with a thin layer of oil & rust.
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I will step out of the shadows for a second...
My thread became a sticky :D
Made this picture a long time ago just never posted it...better late than never
(http://img837.imageshack.us/img837/3146/bmwm42.jpg)
Completely different note, about to get back into e30's after a 3 year dry spell...
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Has anyone thought of taking a look at the fuel pressure regulator. Could be that it's stuck wide open.
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I will step out of the shadows for a second...
My thread became a sticky :D
Made this picture a long time ago just never posted it...better late than neve
Completely different note, about to get back into e30's after a 3 year dry spell...
Nice picture, makes it easy to find. Welcome back to the e30, it's a hard habit to kick, eh?
I'll bet this "CO pot mod" (plugging this cable makes the AFM CO adjustment screw active) could be used in engine swaps, especially where a catalytic converter or O2 sensor wasn't originally installed or isn't planned (like on the track). Say you're swapping an M42 into a Locost or an M10 BMW (320i/2002/2000cs) with a custom exhaust...then enabling the CO adjustment in the AFM by plugging in this wire...it would likely help a lot with idle control and emissions.
While it'd be sloppier than the OEM Cat/O2 system (and I'm all for cleaner air), it'd make resurrecting an old Bimmer that much simpler.
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the cause for my warm start (engine was getting drowned in fuel, it would smell of fuel if i kept trying to start the car) was a faulty FPR since i had already replaced my fuel pump, filter, fuel pump relays, and took care of the hoses under the intake. all i need now is a new ICV.
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I'm having pretty bad issues with this as well, I'm about to head outside and check up on that even though it's almost 11pm over here. I really hope this wire's plugged in.
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Well I know what fixed mine and it will only help you if you hooked the mystery wire up like I did. I disconnected it and all is well.
Lower left corner of this graphic.
(http://img218.imageshack.us/img218/6942/0188ed8.jpg)
Thanks for this, I have been having a random hot start issue that has been frustrating the heck out of me. Everything tests fine going to the starter, but still no start. Idle sometimes is horrible as well.
When I pulled the M20 and dropped the M42 in I connected those wires as I had never seen a M42 harness before and figured they had to be connected...right?
Thanks a ton!
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Well I know what fixed mine and it will only help you if you hooked the mystery wire up like I did. I disconnected it and all is well.
Lower left corner of this graphic.
This is exactly what was wrong with mine! The PO put a clutch in and mentioned moving this harness around, I assume he connected the wires when the cover was off. I unplugged the wire and voila! Much thanks sports racer great to have diagram too!
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Just wondering, if i decat my car, and decided to lose to o2 sensor, what would plugging this wire in do?
and if i decat my car and keep the o2 sensor and leave it un plugged, would it run ok with no cat? surely o2 sensor reads wrong or something?
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Pics from my car if it helps any:
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well crap! ive been trying to solve this mystery for 2 months now, and here it is. i know i plugged that in when i last did a ton of work to my car. i am actually headed out to the car right now to unplug it. thanks!
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I had this issue and found this thread so I decided to check it out. And low and behold the wire was connected. So I disconnected it and it fixed my issue.
Thank you so much for posting and I had to register after that! Glad this is a sticky!
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I can confirm that this trick isn't working on my car. Couldn't it be faulty temperature sensor? Sending wrong signal to the ECU and the ECU thinks the engine is cold and flooding it? Also my car is a bit thirsty. More than it should be, the gauge ks going down too quickly and I won't do many miles for the amount of petrol I'm getting.
Anyway, I wanted to check the sensor today, but couldn't stick the probes into pins to see what's the story between the ECU and the sensor.
And the fuel pump died today. Strange. I stopped at motor factors for something and couldn't start the engine. I was thinking it will start after a while like always but no. Spark plugs dry, then there wasn't anything coming out of the filter when I removed the hose and put on a longer one that I put into a canyster.
(http://i103.photobucket.com/albums/m140/Kingfisher_007/20160405_182035.jpg)
this is how I got home today
(http://i103.photobucket.com/albums/m140/Kingfisher_007/20160405_194504.jpg)
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I think if you have a euro-spec car (assumption based on license plate), then you don't have the O2 sensor and the wire should be connected. You've got other issues.
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Irish reg. Yeah there is no O2 sensor. I have been told in Bmw dealership to look at the idle control valve. Not sure if cleaning the ICV would fix it?
Edit:
Btw you can easily spot the year of manufacture on the plate. It's not 3121.
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Then I'm going to guess 1990. Mine's a 91.
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I think if you have a euro-spec car (assumption based on license plate), then you don't have the O2 sensor and the wire should be connected. You've got other issues.
Agreed, that is how the wiring diagram shows it. I would recommend checking for fuel and then spark ad go from there.
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The whole time the cause of hot start problem on my car was a weak pump. I replaced the pump and now it runs fine and starts every time. The previous pump was obviously weak. Maybe faulty pressure regulator as well? It seems that the car is still thirsty even with a new pump.
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ok, a have a euro spec car with O2 sensor, no cat i guess.Wire is dissconected for now,i have some hot start issues - starting at second attempt . Should i plug that connector back?