E30 Zone

i posted abit abck about my 1988 e30 320i hunting when you stop at traffic lights or after you rev it up.

i have now noticed that if the car car sitting still (at traffic lights for example) it idles fine yet if i drive the car along then take it out of gear & coast it hunts all the time until the car is put back into gear or comes to a stop, the second the car stops moving the idle returns to normal. this may be a very common thing on e30s but im lost & cant figure out how the car rolling or sitting still makes a difference to the idle.

please take a minute out of your day if you can to watch the video.

the begenning of the video (perfect idle) is stationary & then when its hunting the car is out of gear with me touching no pedals. thanks for any help you might be able to give, john

http://smg.photobucket.com/albums/v627/ ... unting.flv

Have you checked the Throttle Position Sensor?

i was told that rolling / stationary would have no bareing on that though?

Check for any air leaks in the intake bellow or elsewhere.

Does the car have a small rubber pipe going from the throttle body to the fuel tank with a valve in it?
If so disconnect it and stick it in one of the holes in the chassis leg.

Clean out the idle control valve.

Then check the thottle closed position, I can't remember what it should be .75mm or something like that.

Umm, I don't think speed has a bearing on the TPS. I stand to be corrected...

Stewart

The question I'm going to ask is: Why do you want to idle your engine when the car's moving?

Brianmoooore wrote:The question I'm going to ask is: Why do you want to idle your engine when the car's moving?

because it should & i would like my car to run perfectly regardless of if the problem is something that happens in day to day driving or only in unusual driving conditions.and the fact it hunts briefly every time the revs fall is a reason to want it fixed on its own.

i appreciate people dont have to try & help me, but brian you are from what ive seen a wealth of knowledge, could you not just as easily have given me some constructive ideas as to the problem rather than ask a question that as far as i can see was asked just to try & be funny & make me look stupid?

the 1st post says that the car hunts when you bring the car to a stop in traffic / at junctions etc & im sure if your car was doing this you would fix it.

stranter thanks for your idea anyway fella

chu ive checked all that apart from the small rubber pipe thing, ill get that checked, thanks

could it be a dodgy AFM ? or airfilter? have you cleaned the throttle body with some carb cleaner etc?

kopite wrote: ask a question that as far as i can see was asked just to try & be funny & make me look stupid?

Not at all. This problem occurs quite a lot with owners of modern cars, who decide that their car has some kind of problem, because they've discovered it does something odd, when they drive it in a way it wasn't designed to be driven.
The answer is always " Well, don't do it, then!"
It is perfectly normal for the ECU to rev the engine slightly just as you come to rest - the road speed signal is fed to the ECU for this purpose. I'm not sure of the exact details of it, but, IIRC, it's something to do with emissions control.
What I'm getting at, is I'm not entirely convinced that your car has a specific problem that won't be cured by a good service and checking out of things like cracked hoses, other air leaks, TPS operation, etc.
I haven't seen your car, and I don't know you. I don't know if you are the type of person who regularly checks out these things and keeps on top of maintenance and servicing, or just opens the bonnet when the engine cries "enough"!

blingsta im in the process of trying to find another afm to try but yeah ive changed the air filter & got the tb cleaned

brian yeah fair point & i obv bot the wrong end of the stick & i apologise.i havnt had the car long (a month ish) i changed the air filter plugs leads etc. the video obviously doesnt show how it is & as you say doing in when rolling is not a problem, but on the rev drop off it comes very veryclose to stalling & if its at the bottom of a hunt (not sure of thchnical term) & you touch the accelrator it will stall. ill keep on with the afm search & see if that cures it, cheers people.