C5 corvette is knocking

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Oct 30, 2024 | 06:03 PM

Nikita_14

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C5 corvette is knocking

I have a 2002 c5 corvette with an auto trans and I can’t figure out why it’s knocking. The knocking tends to get faster when revving in the lower rpms and silent in the higher rpms. The whole car shakes but it’s got an upgraded cam so I’m not sure if it’s normal or not. The knocking also becomes barely noticeable from the outside when the car is warmed up. Any help would be great thanks!

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Oct 31, 2024 | 12:50 PM

helga203

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Oh boy, you have some work in front of you. That sounds like the drive train damage. To me most likely lifter or rocker arm. Start by pull rocker cover.

Oct 31, 2024 | 12:57 PM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by helga203

That sounds like the drive train damage. To me most likely lifter or rocker arm. Start by pull rocker cover.

Lifter and rocker arms are not part of the drive train though......

Oct 31, 2024 | 12:59 PM

helga203

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Quote:

Originally Posted by lucky131969

Lifter and rocker arms are not part of the drive train though......

Valve train

. Im on a bottle of vodka. Thats how i pass my time sitting home listening to wife bitch at me for drinking..

Trust me that's coming sooner then later.

Oct 31, 2024 | 01:02 PM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by Nikita_14

First things first. If you have a knock or loud tap in the engine.......high rpm reving can only make it worse

Start simple
-pull the belt an run just to be sure nothing exterior rotating is causing the issue
-use a mechanics stethocope to isolate the noise
-use an IR thermometer on the exaust to see if you have a colder cylinder

Oct 31, 2024 | 01:02 PM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by helga203

Valve train

. Im on a bottle of vodka. Thats how i pass my time sitting home listening to wife bitch at me for drinking..

Nov 1, 2024 | 07:50 AM

cdee63

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From: In the woods

2024 C5of the Year Finalist - Unmodified

It isn't just piston slap? My 2K auto has a very distinct knock when cold started, can really hear it started in the garage. Goes completely away after a few minutes though it sounds as if yours does not go away.

Nov 1, 2024 | 08:53 AM

Chevy Cust Svc

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If you're unable to pinpoint the knocking sounds, we may suggest bringing it to a Chevrolet dealership to have a deeper diagnosis performed to figure out the cause. Our team can help with that should you need it. Simply send us an email to socialmedia@gm.com to get started.