Xantia Revs up by itself.

JoSawday · Post by **JoSawday** » 09 Jun 2003, 02:48

After a long motorway journey, when the engine is no longer under load , say while wiating ata roundabout with the clutch in, my Xantia revs up by itelf as if i'm getting very impatient with a heavy foot on the accelerator. The rev range being between 3000 and 3500. My local dealer has no solution - do forum members?

wheeler · Post by **wheeler** » 09 Jun 2003, 04:29

engine size/type ?? assuming its a petrol there is possibly a stepper motor or MAP sensor fault

JoSawday · Post by **JoSawday** » 11 Jun 2003, 00:49

Petrol 1.8 SX.
Previous suggestions have been 'oxygen sensor' or 'fuel sensor' whatever either of those are. Main dealer suggests they will only be able to diagnose it if I can get it to their workshop while the problem is exhibiting itself - but I cannot make it happen to order and therefore they will not commit themselves.

drdog · Post by **drdog** » 18 Jun 2003, 21:30

Hi - I had that problem last summer - when the car had this problem then the engine either over reved in idle or stalled.
Most probable fault [same information from two seperate sources: Citroen specalist and a friend who does lots of car maintainance on fuel injection systems] is throtle bypass valve [idle valve] stepper motor.
We've taken it off and cleaned it this lunchtime - so far it behaves much better. Touch wood...
hope this is of help
cheers
Kevin

JoSawday · Post by **JoSawday** » 20 Jun 2003, 03:19

Thanks for this. I'll pass it on to my garage at the next service - at 26,000 miles per year even a 9,000 service interval comes around pretty quickly!