Help Mk 2 Keeps stalling?????

[purple80]

Hi,
I have a 1991 Mk 2 GTi, digifant PB engine code......

The car stalls when approaching junctions? I have also noticed that the engine hunts a bit more, bit of popping and farting (the car, not me) drooping down through the gears.
Occasionally when you start her up the revs leap around on their own, or car sounds wrong (blonde explanation).
I know that Mk2 can have this problem, do I need new ISV?
The car has started to do this more often and is becoming a real pain in the arse.

Any help greatly appreciated.
Charlie

[Dolly]

hey just down the road...

mines also a 91 8v gti and suffers the same kind of symptons although it doesnt stall, when u come to a junction dip the clutch and come off the accelerator the revs dip to around 400-500rpm but then come back up and hunt a little bit .. as for the popping mine has an aftermarket s/s exhaust and when u let it roll along on idle it spits and "farts" but i like the noise 

so far ive changed the ISV the rocker cover breather pipes grommit and regulator valve, and the blue temp sensor not got any better or any worse. im thinking its time to follow the tuning guide that is floating around this forum ..

[purple80]

Where abouts are you then??
Have printed the tuning guide, intend to wave it under hubbys nose tonight.
Sure he'll be well impressed, cars driving me up the wall at the mo, stalls 5+ times a day.
Charlie

[Dolly]

hmmm mines not that bad, i think its definatly worth doing all the tuning stuff im changing my engine in the near future so im not too concerned with it to be honest  .the only other thing that springs to mind is the switch next to the throttle housing i think its like an idle switch i dont have a pic or any more info on it, im sure someone on here does.

[Ktuludays]

what he said ^^^^^^ idle switch on throttle body

there are two switches in series - combined they give an ohmic reading to the ecu.

if one of these or the wiring is on the way out the ecu will sense a wrong signal and the car can idle and run like a bag of nails.

use your trusty haynes which tells you what ohms readings you should expect and how to test them.

top one is for full throttle enrichment and one underneath is for idle.

with engine off slowly open the throttle by hand and you will hear the microswitch click as it opens.

check the plug on the connector the wires can become damaged inside the plastic housing and cause lots of problems.

[Organisys]

Standard advice is : Before u do anything else, replace the blue temp sender with a genine vag one.

[mattkh]

I know that Mk2 can have this problem, do I need new ISV?

Hi
The old ISV can be cleaned out with a carb cleaner.
Also check the vacuum hoses.