Idling

[benjam_in]

Just brought a MK2 Gti and it has a small problem on idle. The engine seems to be hunting for a good idle speed and revs round to 2000rpm then drops right down. Anyone got any ideas of what causes this / how it can be resolved?

[richandhazel]

If you have the Difigant fuel system have a look at table d here:-

http://homepage.ntlworld.com/richandhazel1/Difigant/Difigant%20II%20and%20I%20troubleshooting.htm

I'd go for cleaning the Idle stabilization valve first off.
For more information on the ISV, go here:-

http://homepage.ntlworld.com/richandhazel1/ISV/index.htm

Let us know how you get on.

[Bdub]

I had a simillar problem on my 89 8V.
Cleaned the ISV with carb cleaner - reset the idle ( by turning the idle screw in the throttle body, it's a good idea to remove this altogether, clean it with carb cleaner and squirt some into the hole before placing it.

You then need to start the car - remove the temp sender plug, rev the engine to over 3000rpm 3 times, replace the temp sender plug and rev again 3 times to over 300rpm - idle should now be stable.

This sorted mine.

Cheers