My car is fitted with a Sierra 2.0 8V DOHC with the stock engine management and injection.

Recently when starting from cold the idle has been going to around 1800rpm before dropping back down - if you then blip the throttle, the idle sticks again before dropping.

This carries on until the engine is warm and the ignition has been swiched off once - it then idles perfectly as it always did.

If you disconnect the ISCV wire when its doing the high rev thing it idles at normal idle even when cold.

I think the ISCV is working ok but something is telling it to hold the revs high - any ideas what is what ?

I think it started doing it after fitting a new alterantor belt but cant be sure exactly when it started.

Thanks

Check the TPS is working correctly.

Take the Idle control valve off and give it a good clean out with carb cleaner or similar.

As above, I'd should stall dead with out it connected.