QuestionQUESTION: Hi Nigel, I have a '01 Disco 2 with just shy of 90,000 on it. Just recently it has begun intermittently reving high when it is started after it has been sitting over night. It has just started doing this since it has started getting cooler in the mornings so I don't know if it is temp related or not. I just had the oil and such done, but it started doing that before this. Also, I had a cylinder misfire that was related to a fraying plug wire, so the plug wires have just recently been changed also. I'm not sure if the high revs started before the misfire occured but it definitely started before the plug wires were changed. Any thoughts on trouble shooting this would definitely be appreciated.
Thanks.
Joe
ANSWER: It sounds like you have a high base idle. Have your base idle re-set.
---------- FOLLOW-UP ----------
QUESTION: If the base idle was high wouldn't it do it all of the time instead of intermittently?
AnswerThe engine management system on this model routinely adjusts the idle speed for cold starts. If it is revving to high, you need to start by resetting the base idle so it is correct.
If it were my car, to make sure the system is functioning correctly, I would also perform a tune-up, replacing all worn items as needed, e.g. plugs, filters, etc. and a throttle body induction service. Also check all vacuum lines and breather hoses. Finally, you should also check the engine for codes.
