Rev 3 Turbo Low Idle Revs

[Fixxxer]

Hi there guys. Just need a few pointers as to what could be causing my idle revs to be low.

On startup, it will idle at approximately 500-600 revs, until it is fully warm. At which it will return to a more normal 900-1000. It doesnt ever feel like it is going to stall. And doesnt 'splutter'

Occasionally the revs will idle low at full temerature too, when stuck at the lights for example. A similar 500-600 revs.

I had a brief play around, and when disconnecting the green connector to the Idle Control Valve, the revs will rise and everything appears normal.

Are there any other ways to try and diagnose the problem?

(Rev 3 Turbo, mostly standard other than de-catted with a HKS mushroom induction and BOV. Standard boost)

Any help much appreciated

[jimGTS]

clean idle speed control valve.
id say it was stuck.


remove throttle body, then remove control valve which sits underneath it, then clean it out so the valve moves freely when 12v is applied to the connector.