Hi , please could anyone advise , i have just bought a mk1 1999 focus 1.8 16valve zetec, everything seems fine with it apart from one problem which is erratic idling/revving if stood at lights or while driving.
First odd thing is when you fire the car up the rev counter/fuel gauge etc go to absolute max then drop to nothing then(eventually) to where they should be ??, then the problem continues with the revs , you could be sat at lights not even touching pedals then the car revs up then drops to near tickover but never ticks over perfect ( generally it ticks over round 2000 revs ).
Then if you are driving you can tell revs are too high and if you are say in fourth/fifth but rolling you can feel the revs trying to pull you when you dont want it to.
I have read possibilities it could be such as idle control valve / vacuum hoses etc but could do with a precise indication to the problem because it is getting on my nerves , thanks.