[Paolo]

1996 E36 Compact - Idle hunting / Possible power loss

Hi guys,

Picked up my E36 Compact a couple weeks ago and very impressed with it so far! However, I've got one little problem that I'll try and explain:

- On starting the car from cold/cold-ish it seems to have trouble sitting at the usual idle RPM (just below 1000). It seems to jump up to about 1,500 then dive down to 500 a few times. Lately it's been tending to stall instead of bouncing back up unless I give it some throttle.

- I've seen the same thing happen to a lesser extent when stopped at lights, counter heads up to about 1200/1300 revs then a slight dive before back to the normal idle.

- Slightly more serious, I've had the car seem to drop power for a couple of seconds just after a gear change around town a couple of times, usually from 2nd to 3rd (changing at what I'd consider normal speeds).

Looking around the forums, am I right in saying I should be checking the air flow systems (pipes etc) first of all?

Cheers,
Paul

 

[Davztyr]

a split vacuum pipe would be my first guess..if you cant see any split/perished pipes then try disconnecting your air flow meter to see if its still hunting?

 

[328mark]

check those first and report back...there are a few things it might be if that doesn't sort it

 

[Paolo]

Cheers guys, if I can find said components tomorrow after work I'll check them out and get back to you (not had much time to spend under the bonnet as yet!!)

 

[Paolo]

Update: As luck would have it, car didn't stall on startup today :mad ! Idle speed seems to be a bit lower than I'd expect.

The car did however outright stall about 10 minutes into my journey to work this morning - idling at a set of traffic lights.

I've had a look at the pipes (in situ) and there's no obvious splits, with the MAF out of the equation the car seems to idle a bit closer to 1k, but without the problem happening all the time it's tough to make a diagnosis.

I suppose an option might be to put it into a garage to have them inspect/read codes (not sure how much that costs around here) - anything I should be trying before I consider booking it in?

 

[Ronnie]

Remove the pipe between the MAF and the inlet manifold and inspect it carefully, also have a listen for any hissing from the black plastic crankcase valve which is near the inlet manifold, it has a triangular vent in the top.