2000 revs to zero!

[general_lee]

Although my 4.0HC Chimaera has just gone through a major service, it seems to have developed a fault whereby at random (hot or cold) the revs increase on idle to something like 2000, then suddenly drop to zero. 've read a few notes on Peter Beech's site, but wondered if anyone else has had / cured this problem. Needless to say I have spoken to the garage that serviced the car, but they cant fit it in for another 2 weeks! Any ideas?

[PetrolTed]

Seeing as the problem only occurred since the service, I wouldn't stand for the two weeks argument myself!

[nubbin]

Fluctuations in idle speed are very common with the Rover V8 - it's some valve in the engine that sticks sfter a while, and needs blowing through to release it. I had the same problem, it's easily fixed, and I've had no problems since.

[GreenV8S]

Get yourself a copy of Steve Heath's Griff/Chimaera 'bible' and follow the instructions to clean the idle stepper motor and reset the manual idle screw. That will probably cure the problem. Also consider whether you should find somewhere else to look after the car. I wouldn't put up with people who aren't there when you need them, especially as it's a probem they may well have caused in the first place. Peter Humphries (and a green V8S)

quote:Although my 4.0HC Chimaera has just gone through a major service, it seems to have developed a fault whereby at random (hot or cold) the revs increase on idle to something like 2000, then suddenly drop to zero. 've read a few notes on Peter Beech's site, but wondered if anyone else has had / cured this problem. Needless to say I have spoken to the garage that serviced the car, but they cant fit it in for another 2 weeks! Any ideas?

[trefor]

I've just got the same problem this morning - idles all over the place and cuts out. I'm going to reset the ECU and clean out the stepper motor at lunchtime. I hope it works or I'll have a really horrible journey home (Guildford to North of Slough - lots of stopping/starting). I'll let y'all know. T/. P.S. Interestingly my car was serviced 2 weeks ago too ... and it was at the shop for new brake + clutch master cylinders yesterday. I trust my garage though ... to an extent.

[trefor]

Just been out to the car and my stepper motor was a bit sooty - cleaned it and reset the ECU. Seems to run a bit better now (well better than 2 minutes before I cleaned the stepper). I'll know for sure on the way home. Funny how these things just 'go wrong'. T/.

[general_lee]

Thanks for the replies ... how do you reset the ECU? I've been given a bit of info regarding the location of the stepper, so will have a go at finding that today. Any help greatly appreciated.

[trefor]

Stepper's a 3 minute job as long as you have an adjustable wench :-) to loosen it off. ECU is located either alongside or on top of the battery box. Take the footwell carpet bit out and you'll see it - a black box with a big multi wire connector -it's easy enough to undo, leave it for a few seconds and plug it back in.