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Rev Fluctuation

Maddog309

By Maddog309,
in Engines & Forced Induction

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Maddog309 Apprentice

Maddog309

Posted
Posted

Hey guys, my s2 r33 is running completely fine after its recent rebuild, just one problem. I've been noticing, when the car is warmed up, if I stop at the lights of pull up in the driveway, the revs will fluctuate, doesn't sound real nice. Could this be anything to worry about, or could it be something small? such as a dirty air idle control valve? any input would be fantastic. Tried looking up previous threads before asking this, and couldn't find any relevant info. Thanks again.

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scotty nm35 Grand Master

scotty nm35

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Posted

From my experience the iac valve tries to target a lower revs, but any small vac leak can stop it hitting that target, which gives you that cyclic idle as it tries again. Even a small hose leaking is enough to cause it.

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