Replaced cracked intake manifold, now knocking at wot

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08-27-2014, 10:41 PM

kast1376

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Location: Sacramento

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Replaced cracked intake manifold, now knocking at wot

Need some educated guesses here! Recently replaced the intake manifold, and now when I go WOT, I get knocking. No knocking otherwise in any gear at any speed or at idle.

Any ideas?

08-31-2014, 02:46 PM

JC316

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Location: DFW, TX

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Why did you have to change the intake? Best guess is that you have a vacuum leak that's leaning you out and causing detonation.

08-31-2014, 04:56 PM

bluebeastsrt

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Vacuum leak! End thread.

08-31-2014, 08:34 PM

kast1376

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Location: Sacramento

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The intake cracked where the plastic joins with the aluminum cross over. Will start looking for a vac. Leak somewhere. Thanks guys!

08-31-2014, 08:37 PM

99GTvert

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That sucks. Did you use new gaskets for the intake? All your hoses plugged in? Is the new intake itself alright?

08-31-2014, 08:49 PM

uberstang1

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Location: wilkes-barre PA

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check the new intake for cracks as well, if u have acces to a vacum smoker thats your easiest way to find the leak.

09-01-2014, 02:08 AM

kast1376

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Quote:

Originally Posted by 99GTvert

That sucks. Did you use new gaskets for the intake? All your hoses plugged in? Is the new intake itself alright?

All new gaskets, all hoses plugged in.

Uber, what is a vac. Smoker?

Edit: I wish I had access to a smoker! I really hope the intake isn't f%#ing cracked. If it is hopefully AM will replace it.

It's gonna be hard to track down. There is no issue at all until WOT, so I don't think the standard carb cleaner check will work.

Last edited by kast1376; 09-01-2014 at 02:17 AM.