Idleing Problems

[mikeamtrak 0]

I know this has been done to death and I have searched, but none actually match my problem, on other threads it either hunts up and down, idles too low or idles too high, well mine does all three and in no particular order , just randomly changes to the point I have to alter the idle screw! Sometimes too low and cuts out sometimes too high sometimes up and down, sometimes sounds like running on three pots, sometimes white smoke not much and sometimes clear as a bell?..

 

Changed spark plugs, afm, throttle housing, still the same,

 

Running induction kit and aftermarket exhaust, no other changes that I know of...

 

Oh it's 1.9 1991

 

[Anthony 1,003]

Given that you mention white smoke and dropping to 3 cylinders, Is it losing coolant and/or pressuring the cooling system?

[mikeamtrak 0]

No it's not losing any coolant, not checked cooling system pressurising, and it was only once with a bit of white smoke and when I revved engine it cleared

[Slo 283 1 Cars]

I think 99% of us here have had this bloody annoying ghastly feature that the 205 gti has inherited, i would say the....

first thing to check is the bolt that attaches the oil filler housing to the inlet manifold is tight and not letting air in through the threads, use some thread lock on it to be sure

secondly clean out all the rubber air pipe work and use copious amounts of wd40 or b&m cheap crap equivalent around the throttle body to get it sparkling clean inside

third check your sad pipe work hasnt popped off anywhere especially the lowest one that fits on underneath as on mine it had come off there as its not got a ridge on the end to stop the pipe popping off and my engine was doing the same as yours when i got it

fourth check throttle position sensor for the 'tick' when you touch the throttle and/or use a multimeter to check if its working

[mikeamtrak 0]

Thanks I will check all the above, any more suggestions just incase it doesn't help.?

[Carbs4me 45]

Does it smell like unburnt fuel when running by any chance?

[Tom Fenton 1,548]

As above. Also remove the idle screw completely and clean out the passages through the throttle body. Also check for wear in the throttle body butterfly spindle and bushes.