Hi guys, I'm having problems with my 1.8 Zetec Escort. When the motor is started from cold the engine revs keep pulsing. Its rather like an uncontrolled oscillation, the revs pulse up to 1000 revs and then drop down till the engine almost stalls, then the revs shoot up to 1500 and drop back down again, then upto 2000 revs. But when the revs drop back down quite often the engine just cuts out. I've cleaned out the idle speed control valve which i was hoping would solve the problem. Sadly not! Once the engine has run for a few minutes it is totally normal.
Can anyone give some advice of possible causes of this?
Thanks, Rich.