Reading through the forum i see this is a common problem.My 440 1.8 slowly rises on tickover from 900 rpm to 4000 rpm?!!. If i blip the throttle this sometimes sorts it out and it drops back to 1000 rpm. Have changed the air filter and no help?. Any ideas on this one. the car had a full sevice just 2000 miles ago with all things changed ie plugs, filters, leads, fluids, Any help would be appreciated.
cheers :460:

In my case it was the oxygen sensor- otherwise called the lamda sensor- on the exhaust. if this isnt working it can confuse the ECU and cause the tickover problem.
Grendel

fault finding says it is the idle control valve.are these easy to replace??
hope they are as it is a pain to drive at the moment.
volvo say £100+vat+ labour!!!

Thats the equivalent of the throttle on a carburettor, as I recall its pretty easily accessible and I think has rubber tubes both sides (or one side at least- from memory).
Grendel

:banana: Got a new idle control valve fitted for a tenner although the valve wasn't cheap!!.
it's an unbelivable change to the car,drives like new ish.Apparently this is one of the most common faults on the 400 series (this bloke does two or three a week)!! they have a step motor in them and eventualy they wear out,thus causing all sorts of throttle problems as the car can't idle or decellerate properly.If you look in the haynes manual section 4 it tells you about them and how to change them.


Thanks for the advice anyway.
cheers steve.