Official Engine Stalling Thread

[marcusantonus]

Update...basically switched out the old MAF with a used one from EBAy and it solved the problem. The ObdII reading for P0103 was good indicator...so my 850R is up and running again..

M

[MatDesign84]

Has anyone thought about re soldering the computer in the car? I know solder gets old and an older man told me thats how he got his e30 bmw to quit doing it. I might consider it myself. I am stalling daily usually once or twice within the first few miles, highway or idle. I have rebuilt the fuel pump relay thanks to this site, replaced the cmp sensor, cleaned the IACV and cleaned the plugs. I have been told to look into the Engine temp sensor and the mail fuel sensor. I have also replaced the selinoid. Still it goes on and its un safe I can rely on it to start and hold up traffic im bummed out. it will not start for about 3-5 minutes and it only does it in the warm months. This has been going on for a year.

[MadeInJapan]

...and what are your codes? Without knowing what part of the computer is bad, I would be hard pressed to even plug in the soldering iron. The ECU's on these cars very rarely are the problem.

[Volgrrr]

Good day, all,
.... also has difficulty starting at times. All of this has occurred regardless of outdoor temperature or weather conditions. By "difficulty starting," i mean initially the car makes that "whirring" noise, then after waiting a few seconds a re-attempt is usually successful. Also, sometimes following the whirr comes a muffled "thuddish-click" which resembles the sound of a large electrical breaker being shut...like some physical component under the hood has just reset itself and rotated into another position. After that noise is heard, the car ALWAYS starts up.

but if anyone has an other suggestions, I'm open to them. I just want my car to work again. That's all. Is that too much to ask?

I know this is a bit late but if the ignition switch has loose wires/connections or something similar it could cause the vehicle to falter or stall by interrupting the supply to the ignition circuit (just the same as you turning it off with the key).

Also a couple of attempts at starting (i.e. turning the key on and off) you might get these loose wires/connections to make enough contact to activate the starter solenoid which could engage with a 'thunking' sound but result in the engine turning over.

Just my 2 cents worth.

[MatDesign84]

...and what are your codes? Without knowing what part of the computer is bad, I would be hard pressed to even plug in the soldering iron. The ECU's on these cars very rarely are the problem.

No codes.

[MadeInJapan]

I'm apt to think that if part of the ECU not making contact is the problem, you would get a code specific for that. There are a bunch of "ECU not communicating" type of codes. My personal opinion is that your problem lies somewhere else. It's usually something very simple- bad or intermittently bad fuel pump relay, a chafing ground wire, etc.

[topherez]

The Problem: My car began stalling intermittently when I am coasting. I was usually lucky enough to have the time to throw it in neutral, turn the ignition on/off a few times and start it before I became a traffic hazard.

I checked a lot of things... MAF, distributor cap, crank position sensor, etc. but found it was something a lot simpler... a vacuum elbow.

Here it is


And here is the new one


It could be a lot of things (and who knows, the problem may creep back up), but it runs a lot better now, and hasn't stalled since.

[MadeInJapan]

Nice! Thanks for sharing

[roberte]

I bought a used 94 850 wagon 2 years ago and started have similar problems right away. Mostly when slowing down from a freeway exit, I could also duplicate the problem by revving the engine to 2.5k RPM for a few seconds and abruptly release the accelerator. I started with the usual stuff, replaced the fuel filter, and while replacing the air filter I noticed the hose from the air cleaner to the intake manifold was cracking and had many holes. After wrapping it with duck tape it ran fine. Shortly after I replaced it with a new one from the dealer. 2 years later now the problem is back but in that it won't start back up until it cools down. The problem is happening more frequent now, even when idling at a red light.

It seemed to me like a flooded engine like in the old days. The more I tried to start it the more it refused and the longer I would have to wait. Just for fun I took out the #2 fuse for the fuel pump and it started and ran for 5 seconds. Replaced the fuse and it starts back up and runs normally. This seems to always resolve the problem, but it is embarrassing having to pop the hood in middle of traffic and run back and fourth a few times.
Is it possible to have too much fuel pressure and flood the engine on these?
I'm tempted to wire a momentary fuel pump kill switch, but with the problem happening more frequently I know it will only be a temporary fix.

I've read through this very long and informative thread and am going to clean the throttle body and replace the capacitor in the pump relay tonight.
Seems to happen more on hot days than cool days. Temps here are 110+ and will be that way for the next 2-3 months.
There are no ECU codes to report, so I'm holding off on the cam position sensor for now.

Update (2 July): Cleaned intake manifold without removal, engine runs better but stalling persists.
I replaced the 100u 16v capacitor in the 103 relay with a 100u 25v and so far today no problems. Also re-soldered all components on the relay board (some looked half soldered) and sprayed the relay contacts real good with MG Chemical's Cleaner Degreaser (CAT# 4050-525g)

Update (3 July): Drove car all day in 114 deg weather and no problems to report. Interestingly the AC worked better than usual.

Update (7 July): Nothing to report, car is running great.

[matthew1]

I'm closing this thread because it's getting too big/too broad.

If you have an engine stalling question, please start a new thread.

Thanks,
Matt