RPM fluctuation after WOT

3xBlackCobra

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So I went WOT in 3rd gear today, then went to neutral to slow down. While in N, I noticed the RPM's started fluctuating between ~450 and 1,200 in a fairly steady pattern. My initial thought is that there may be a vacuum leak (or even an ECU issue?), but wanted to hear from anyone else who may have ideas. I didn't notice any fluctuations once I stuck it in 6th.
 

MG0h3

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Thats typically going to be in the tune. IAC is probably hunting around a little bit after you snap the throttle shut. Might have a lazy IAC but considering all of our cars are tuned thats what I would expect it to be.
 

Phil04Cobra

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Clean your IAC with some throttle body cleaner , make sure the little valve isn't stuck as well. I'd also check the throttle positioning sensor.
Make sure it's set properly.
 

3xBlackCobra

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Clean your IAC with some throttle body cleaner , make sure the little valve isn't stuck as well. I'd also check the throttle positioning sensor.
Make sure it's set properly.

I'm going to try this after work today. I'll do another couple of pulls to see if there's any difference
 

Phil04Cobra

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I'm going to try this after work today. I'll do another couple of pulls to see if there's any difference
I find it helps. Especially if you're not running a catch can , oil residue gets in there and can clog it up. I spray throttle body cleaner in there then clean it out good with a q tip.
Do the same with the throttle body.
I'm installing a catch can on mine soon.
 

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