Very high idle speed????

[dan69]

Hi, my '89 scirocco GT2 has started idling at about 2400 revs for the first 5 to 10 mins after starting up, its getting a bit silly now as i dont need to use the throttle when drivin through town its like having cruise control. but after running her for a while she'll drop back down to her usual 900-1000. she hasnt lost any performance and is still happy cruising between 80-90 on the motorway. She is getting slightly hotter than she used to also, not sure if thats to do with the idling speed or not?? Does anyone know what the problem may be?? Cheers

[go-for-it1]

Fit a new waxstat on the water pipework on the front of the carb. You'll need to take the air filter box off to see it. Black plastic bit with two hoses on it and screwed to the carb with 2 philips screws.
Rob

[dan69]

Cheers for that.
Would that also be why she keeps going sometimes after ive turned her off?

[go-for-it1]

Running on after switching off can be many things, timing to far retarded so spark is after top dead centre causing fuel to burn in exhaust, fuel mixture to rich, Pierburgs have a little round electrical shut off unit on the back (drivers side) with vacuum hoses going to it which is supposed to stop running on but these fail or the hoses perish preventing it working properly. Also carbon in the head can be hot enough to give a spark during run down even though ignition is switched off, head off and decoke is the solution to this but sometimes a good spray of carb cleaner down the throat of the carb whilst at high revs works. Hope this helps.
Rob

[dan69]

Brilliant thanks for your help, looks like its gonna be a busy bank holiday for me!