idle problems

[Sean-p 10]

So i have a 2.0 16v and the problem is it some time struggles to idle once turned on but then will be fine but when it warms up it starts to idle at 1800 but if i blip the throttle it some time settles down again but its not been settling down recently

 

Could it be metering head ?

 

Also when it warm and idle normaly it revs up and down i had a vw mechanic look at this when i originally put the engine in and he didn't know what it could be

 

Any help would be appreciated

[bmwcompact 10]

Sound like the ISV (idle stabilization valve). You can try cleaning it with brake cleaner. That may fix it or even make it worse but should indicate if thats you problem. Mine got cleaned a couple of times and then was replaced with a used one.

 

Sometimes however its the potentiometer on the throttle body thats the problem. It tells the ECU when the throttle is closed (ie that the engine is idling) and the ECU then controls the ISV. Again it may have to be replaced with a used one. (new ones cost silly money)

Edited March 27, 2013 by bmwcompact

[Sean-p 10]

Thank you very much :-) i will have a look this weekend as it happens i have a spare throttle body under the bed :-P so i can try that as well

[james153 0]

I agree with BMW, only thing to add is that you can test the ISV electrically to. if you unplug it and put a multimeter across it you should get between 4-12 ohms iirc. :)

[dannyboi 10]

i need some help too on this

 

ive got the same problem with my vr6,

that struggles to idle when cold but even when warm it only idles at 650-700,

also if im driving along when i change gear it sometimes revs by itself between 2-3k up and down? to stop it i have to rev it over 3000 and it will then go back to idling at 650-700

 

before all this happened it would run fine and idle at 900 when cold no problems

 

thanks

Edited April 4, 2013 by dannyboi