On advice of the group, I recently fitted a new idle speed control valve to the Cav 2.0 16v, 1995 vintage. Whilst doing it I decided to remove and clean the throttle body thoroughly. I removed the throttle potentiometer to avoid contaminating it with carb cleaner, but when refitting I found that the screw holes are much larger than the screws, hence allowing a significant amount of anglular variation when fitting.
I fitted it with the screws centrally in the holes, but the engine still doesn't idle properly and also now runs slightly lumpily when the revs are raised above idle with no load. The tailpipe has become more sooty than it used to be, but fuel consumption is still reasonable at about 37mpg average and there are no abnormalities during driving, except for the idle speed remaining too high.
Once again there are no fault codes present. Any more ideas before this ends up becoming like Peter's pinking thread!? Could it be the air-mass meter again? It was replaced about 2 years ago though. All breather pipes are clear too.
cheers James of Sunderland