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3k idle after first start

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Old May 27, 2009 | 10:59 AM
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Default 3k idle after first start

Recently, I removed my LS1 manifold, but had to reinstall it due to something that came up.

I plugged back in everything that I could find. Bolted down everything. Everything looks good to me. The only difference is that I have a new OPSU, and I ported my TB. Upon the first start, my car idled at 3k rpms. I let it idle for about 10 seconds before I shut her down. The battery was disconnected during the manifold swap.

Any ideas? Could this be a vacuum leak in the intake? Everything ran fine before, and the seals all looked good.
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Old May 27, 2009 | 11:07 AM
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Originally Posted by Siphon
Recently, I removed my LS1 manifold, but had to reinstall it due to something that came up.

I plugged back in everything that I could find. Bolted down everything. Everything looks good to me. The only difference is that I have a new OPSU, and I ported my TB. Upon the first start, my car idled at 3k rpms. I let it idle for about 10 seconds before I shut her down. The battery was disconnected during the manifold swap.

Any ideas? Could this be a vacuum leak in the intake? Everything ran fine before, and the seals all looked good.
Yes it could be a vacuum leak. You are getting some unmetered air from some where.
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Old May 27, 2009 | 11:09 AM
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Could be overporting on the throttle body. Did you drill out the hole in the blade or knife edge the blade?
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Old May 27, 2009 | 11:12 AM
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I ported my throttle body well within reason. It could actually be ported a good bit more, but I didn't want to overstep the boundaries.
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Old May 27, 2009 | 11:12 AM
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Did not touch the TB blade at all.
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Old May 27, 2009 | 11:14 AM
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Originally Posted by Stang's Bane
Yes it could be a vacuum leak. You are getting some unmetered air from some where.
To remedy this...would I have to completely take off the intake manifold and reinstall? Or maybe just tighten some bolts more?

Also, I noticed, when I turn the key, I hear a small grinding that I never had before, from what I'm guessing is some sort of fuel line/pump related from under the hood.
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Old May 27, 2009 | 11:20 AM
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Originally Posted by Siphon
Did not touch the TB blade at all.
hmm. I had my idle just to 3200 rpm at one point but that was do to rediculously cold temperatures and a frozen Idle air control motor. you may try spraying some TB cleaner in the IAC vent to see if maybe it's stuck. No guarantee but hopefully it'd stop you from having to completely remove the manifold.
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Old May 27, 2009 | 11:24 AM
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This may be related, but I just noticed that my gauges move a lot faster when the car is turned on and off. They almost instantly go into their places.
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Old May 27, 2009 | 12:18 PM
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Found the problem. The TB blade isn't closing completely. I started the car and forced it back, and it idled fine. Guess I'll have to find another TB. Thanks for the imput
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