325i idle / driving problems

[FLIP]

I don't know much about cars, but I have been checking up on other forums about this problem.

1992 e36 325i 110,000km

When I drive to school (15miles), I would get stuck in traffic just before the campus bridge. My car would stall in traffic, 2-3 times on a bad day. The idle is rough and sometimes everything just 'dies' for a second and/or stalls. Parking the car in the lot, driving 1 mile an hour (just closing the gap from the car infront of me), my car would stall. While parked, the car would idle at about +500rpm and it would bounce and you could feel the engine bounce around and at the same time, the headlights would dim. Sometimes driving at 30mph, all the gauges would die out and the engine would freeze, then it would 'cough' and return back to normal.

I had this checked at a bmw/benz/audi specialist. New fuel pump and refurbished ECU was installed (~800 for both + labour). The problem seemed to be fixed, but right after the ECU warranty expired, it started to do the problems again.

Now I am reading info that it could be: idle control valve, sparks /or ignition coils, o2 sensor, etc.

Before taking it to the stealership as a last resort, what do you think is the problem?

[cbouchez]

it's probably the o2 sensor. Che the fuel first of all. Next time you put gas on your car get the octane booster. and put it with the higher octane available at your gas station, do this three times. If the proplems persists check your O2.

BTW: How is your fuel economy?

[bol]

My 318 used to do this a lot. I had to replace the O2 sensor.

The problem for me was caused by touchless carwashes. The high pressure water would get into the ECU and O2 sensor. My car would barely run after that. Take the ECU out of its compartment and see if it's wet. When I cracked the case of mine open it was very damp inside. After drying it out and replacing the O2 sensor all was fine...


I now avoid touchless carwashes!

[FLIP]

I use 91, used that booster stuff. We thaught it was fuel freezing, so we also used gas anti freeze. We also tried fuel injection cleaner (been using the stuff before and after it happened the first time). I believe it is the o2 sensor tho or fuel filter. Today it seemed really bad, I would just start the car and the rpms would bounce from 600, 'stall', then jump to 1000, over and over and over. Would this seem like o2? Fuel economy... from half tank to 1/4th is about 150km. So its about 10km/1L.

[bol]

Definitly sounds like an O2 sensor to me. I'd start there and work up. The car should produce a code however. You can check the codes on your car by following the directions here:

http://www.unofficialbmw.com/repair_faqs/motronic.html

[FLIP]

the pedal test does not seem to be working.

[talisman]

i'm having the same problem thanks for the hints

[FLIP]

I just fixed my problem (this thread is sooo old).

Changed spark plugs with Champion coppers (cheap price plugs) and all the problems went away. The only thing I noticed that was different was when I floored the car and hit the downshift button on the pedal, the strength of the pull on the highway seemed slower, but then again I changed my wheels to 17"s, not if that makes any difference..