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Well lately something funky has been going on. She can sit and idle at 700-800rpm with no problems, there's no fluctuations. I can press in the clutch and nothing happens, but when I put it in gear with the clutch disengaged then it'll go between the comfortable idle and up to 1500rpm. Then it'll drop suddenly back down to the idle. Whenever it drops I notice the lights dim a little bit too.<p>What is going on... it does this even after cruising and pushing in the clutch, it'll drop down to 800, rise to 1500, then drop again. Suggestions? Ideas?

I've noticed that, when coming to a halt, say at the lights, the idle revs stay high (maybe 1200) for a bit, then drop to 900, then drop again to 700. I've assumed it does this on a timed basis, based on detecting neutral. I think your car will have the clutch and neutral switches wired to the same ECU point (different in UK - we don't have the clutch switch connected). This is the only connection I know of between clutch, manual shift and engine control. This is just guesswork, but maybe one of the switches is playing up?<p>When the revs drop its normal for the lights to dim a little.<p>[ March 02, 2003: Message edited by: IanL ]</p>

I had some similar idle fluctuation issues. I took it in and had the idle screw adjusted. Took about a good 45 minutes of testing, adjusting and driving before things were back to where things should be.