318i intermittent idle and acceleration problem - BMW Forum

Harri9102 · 06-29-2010, 04:46 AM

Hey guys

After fixing my startor motor issue my 94 e36 318i ran perfectly fine up until a few days ago.

So i was driving along and i suddenly lost the power to accelerate, if i pushed the accelerator to the floor the revs did not go up at all, however if i pumped the accelerator 4 or 5 times the revs would go up to about 3000. So i pulled over onto the side of the road and the revs dropped to about 200-300 and fluctuated around there and the car was barely turning over.

However this issue is very intermittent as i can start the car when cold, and drive for a few kms and then have the issue occur. Or i can drive for a 100m and have the issue occur. I can then turn the car off for a few minutes, turn it back on and it will be idling perfectly fine and drive fine but then have the issue occur again a few minutes later if its still cold.

One thing to note is that this only happens when the car is cold, when it warms up it is perfectly fine. Which leads me to believe that it is a sensor of some sort, perhaps the O2 sensor or maybe the MAF sensor. I replaced the fuel filter so it was not a blocked fuel filter.

YouTube - BMW E36 318i idle problem

This video is showing the idle problem and you can hear me pump the accelerator all the way to the floor about 5 times and yet the revs only go up to about 3000. If i don't touch the accelerator then it fluctuates at the very low rpms and eventually just stalls out.

Any help with this issue would be much appreciated.

Thanks guys.

witeshark · 06-29-2010, 09:30 AM

Have you checked/cleaned the MAF (intake airflow sensor)?

Harri9102 · 06-30-2010, 12:35 AM

Thanks for the reply

I took a look at the AFM however it looked to be pretty clean anyway. No junk and no build up of carbon in it. Maybe the sensor itself is just faulty? I might clean it anyway just to be on the safe side.

Thanks again

witeshark · 06-30-2010, 09:32 AM

How about the fuel system?

dman24 · 06-30-2010, 11:31 PM

you might wanna pop the hood at night and look for some arcing from the plug wires. i had a very similar problem and it was just plug wires lol

Harri9102 · 07-01-2010, 02:04 AM

I can't say I've checked the fuel system all that much, perhaps i should do that

Alright I'll have a look at the plug wires tonight

I went to the mechanic to get the error codes read, and it spat out error 36: fuel tank evaporation valve and error 70 and 201 which are both o2 sensor related.
He cleared the errors and I'm going back again soon as some of these errors may have been from a long time ago, even though i heard the DME clears the errors after 60 successful starts?
However i think the main culprit from this is the oxygen sensor.
cheers