Intermitant tickover

[dowen]

Can any one help? My 98 2ltr xm sometimes has a job to maintain tickover, at trafic lights, it sometimes stalls, I can hear the engine trying its best to settle to a steady 800rpm but it seems to rev up and down, sometimes it settles, and sometimes cuts out. Otherwise the car and engine run really smooth.
Ive checked for air leaks, and a diagnostic came up with no faults. Any one got any ideas?
Cheers, Dave.

[Dean]

Hi Dave

Sounds to me like a sticky idle control valve, it wont give any fault codes but will allow tickover speed to jump about all over the shop if its full of muck, there is good and bad news however...

To test it, spray carb cleaner or wd40 in it and turn the valve manualy taking care not to score the valve assembly to really work the muck out, if the valve was sticking when you put it back on the car all should be well or at least much improved, thats the good news.

The bad news is that once they get to this stage the shock of a good clean out usualy kills the valve stone dead within a few days or weeks, you may be lucky but if its messing aroung chances are cleaning will only buy you a couple of weeks trouble free service and new ones are about £70-£100.

D

[dowen]

Hi Dean Thanks for that. I did what you said, and its like a new car, for two days anyway! However , as you said it might, it stalled.

I found one on EBay £29 +post, not nuch of a job to fit.
Many thanks for your help.
Rags. Dave.

[Dean]

Hi Dave

Glad you found one at a good price, and thanks for posting back

D