Bad idle & stall, taking maf on/off helps, why?

[Jonas_R]

Oki this is very weird.

I have really bad idle and the car almost stall every time i press the clutch down or it simply turns of.

However if i take the maf off with the engine running for say like 5-10 seconds and then put it on again. The car runs much and does not stall i think this is very strange? Any body that can explain this? Maf is brand new, only 6 month old.

/Jonas R.

[Sidspud]

Sounds like the ISV (Idle Stabilisation Valve)
Either clean it or replace it.

Its the aluminium cylinder that sits up behind the throttle body area.
BTDT

[Jonas_R]

It aint the ISV, it is brand new. And i tried cleaning it did not help a bit, i also tried unplugging it and it made it worse. So that is definately not the problem.

However if anyone can tell me what happens when you disconnect MAF? Does the ecu run on a different idle/full program? Because taking it off fixed the problem and putting it back on after 10seconds does not restore the problem. The problem only comes back later say after some hours. It seems to me like unplugging maf resets something and after a couple of hours this is back to status que?

/Jonas R.

[Fat Audi 80]

Sounds like the Maf is faulty as when it is disconnected I beleive the car will run with generic / get you home parameters.

I am sure someone with more knowledge will be along soon though....

[Jonas_R]

Well that is just it, how long does it take before the ECU changes from get home values to normal values/normal use of MAF? because it does not change the second i plug the maf back in.

/Jonas R.

[s2_bo]

try resetting the ecu (removing the fuses under the red fuse clip in fuse box for a few mins)

I had the same problem about a month ago.

After replacing the Maf it is now fine.

pain in the **** though!

[DamoM]

In my experience, the car will idle fine with the MAF removed but as soon as you hit any kind of positive boost the power is cut suddenly.

My car still idles and stalls badly. I have been running it with the ISV disconnected (which I have changed along with evry other possible cause!) and it idles much better but part throttle driving is a bit jerky - better than it stalling all the time though.

With my ISV connected it idles fine after engine is started, hot or cold, and after a while it will not idle at all. If I turn off the ignition and retsrt the engine it is fine again for a while. Means that the ISV and everything else is fine but kind of points to a bad connection somewhere I guess. Have kind of given up looking for it now because it is such a damn ball ache!

[mastermind]

Is thre MAF on properly with the O-Ring
Sometimes spraying contact spray on the MAF plug helps the contacts which could be eroded.