mk 1 gti cold start fault ?

hi guys,
got a problem with my car when its cold !
it starts first time but wont idle until its warm ? it will stay running if you hold the revs up but as soon as you let the revs die it cuts out ! once warm it idles fine.. any suggestions ? its a mk 1 gti 1.8..
thanks

starter for 10;

how about leaky injector seals?

spaceace said

starter for 10;

how about leaky injector seals?

wouldn't that affect it when it is warm as well ??

mixture might be out to compensate for the air leak.

I'ts easy to check, just pop 'em out. the o rings shouldn't cracked or shrunk.

WUR would that not play a part in this? my car does the same, as when it cold it starts straight away but then idles very low but once up to temp holds the revs a dream.

i have a spare WUR that im tempted to chuck on, but ill also have a butches at the injector seals

Aux air valve is probably the culprit. Check it form cold by squeezing the pipe from it to the manifold. They revs should fall when you squeeze. If not then the valve is stuck. If they do fall squeeze again when hot and the revs should stay the same. If they fall the valve is stuck open.

HTH.

i have this problem also (on a 16v engine), cuts out without throttle on initial cold start, however it idles fine after about 30/40 seconds of keeping the revs up, it then settles and idles fine.  Also once the engine is warm, will start and idle ok first time.  not sure how blind i am being…but where/what exactly is the aux air valve? Thanks.

bpd said

i have this problem also (on a 16v engine), cuts out without throttle on initial cold start, however it idles fine after about 30/40 seconds of keeping the revs up, it then settles and idles fine.  Also once the engine is warm, will start and idle ok first time.  not sure how blind i am being…but where/what exactly is the aux air valve? Thanks.

A lot of the 16v conversions don't fit the aav or iac so you may not have either fitted… (aav is off the mk1, iac is off the 16v).

aav is at the back of the manifold on the off side (rear left as you look at front of car.