My girlfriends 1989 gti 8 valve (digi) has been having a few issues with an intermittant sticking idle. Virtually everything ignition wise has been replaced or swapped (blue temp sender, leads, plugs, vac hoses, AFM, ECU, ISV etc, etc). Car has had timing and mixture set up. The garage that did the recent MOT reckoned it was a worn throttle body, so I have tried a couple of second hand ones. I fitted a very decent unworn TB today (off another forum member) during my lunch hour at work and so far no sticking idle issues!! However if you rev the car at idle by blipping the throttle the revs rise quickly and drop quickly to about 1200 then rise very slightly and then drop slowly to about 900rpm??? Anyone know why this would be? Is it an ISV fault? The reason I ask is because my gti idles perfectly, never sticks and if it is revved at idle it drops steadily to 900rpm with no hiccups?? It does have a Kent GS2H in it though!! Any ideas??? Cheers Alpenweiss2
Mine started doing this yesterday randomly whilst stuck in traffic. I will try and check the vac lines over the weekend maybe something is damaged or has fallen off. My car done this in the past but I cant remember how/if I fixed it or if it fixed itself. I hope that shiny TB was ok.
How do you go about checking this? Do you mean the wiring that is part of the TB or the wiring that connects to it via the black plastic two pin connector?? It is difficult to see the route of this wiring as it is fixed to the bulkhead and behind loads of crap ?? Cheers Alpenweiss2
the 2 pin plug thats hidden behind loads of crap all the crap might be hiding some wire damage so need to get in there and investigate. you should see 5v across the pins with the ignition on
Out of interest, when it's sticking, if you pop the clutch out slowly until on the verge of stalling does it drop back to 900?
