Random high idles

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May 15, 2020 | 10:42 AM

Chris86581

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Random high idles

Morning everyone, i have a 2004 z06 that has random high idles. when i start the car sometimes it jumps to about 1800 RPM then stays there 10 sec before going down to idle. when coming to stops or red lights sometimes it stays at 1800 ish for about 15-20 sec before coming down to idle, could this be a vacuum issue??? car has a LS3 swap and cam with the LS2 silver blade TB and has been tuned recently.

May 15, 2020 | 11:13 AM

helga203

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Quote:

Originally Posted by Chris86581

I would put my money on vacuum leak. Dont really know anything out of the blue can cause that. Get starter fluid and start spraying manifold all hoses to brake mc the big hose. See what happens.

May 15, 2020 | 11:53 AM

Chris86581

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Is it safe to do that with starter fluid?

May 15, 2020 | 12:07 PM

C5 Diag

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I'd take the car back to your tuner !!

May 15, 2020 | 12:11 PM

runner140*

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Quote:

Originally Posted by Chris86581

Is it safe to do that with starter fluid?

Or use a small tank of propane with a long rubber hose.

May 15, 2020 | 02:52 PM

feeder82

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I'll second the tune as a issue, idle quality is tricky to tune.

May 15, 2020 | 06:14 PM

helga203

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Quote:

Originally Posted by Chris86581

Is it safe to do that with starter fluid?

Yes do it all the time. Just came from outside tracking a high idle and we found it with starter fluid, but if your not comfortable dont do it. Yes back to tuner like they said. I bet they will say its not there tune. Been there done that but you might have some good guys. After i had mine tune ran similar to yours brought it back they took it for 30 mins and said it was fine we made adjustment. started it up and all they did was turn the idle up to 1k rpm then they tried to charge me 200 more. They will never forget me after i spoke my mine.

Last edited by helga203; May 15, 2020 at 06:19 PM.

May 15, 2020 | 06:23 PM

Chris86581

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@demon666 yeah had some TB issues before so idle sucked, after new cam/TB i took it back twice cause idle was odd. theres not many tuners near me unfortunately.