Piston Slap at startup?
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Joined: Jan 2015
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From: Louisiana
Piston Slap at startup? Is there anyway to quieten down the piston slap at startup? I have a 2002 SS Camaro with 109,000 so I'm sure there is a healthy carbon deposit on the pistons. Is there a way to clean this off that would work? If you've gone through this and have some ideas I'd appreciate it. Thanks for the time!
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Joined: Sep 2005
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From: NYC
There is nothing you really do until you rebuild it. Mobil 1 0W40, Rotella T6 5W40, etc might quiet it down a little. The carbon can be cleaned by adding Techron, Seafoam, etc to the gas tank when filling it up.
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When the engine is cold the carbon can contact the head surface and be very noisy. If that's what you are hearing its NOT piston slap. Piston slap is a slight diesel engine type sound most all gm engines of this type have.
You are hearing cold carbon knock, as the engine heats up the heads and block grows away from the pistons and it stops knocking. I've had good success using different carbon cleaning products but you may want to try carbon cleaning service from a dealer. The add a bottle to the fuel tank type stuff doesn't work that well and I'll bet your intake manifold is CAKED with carbon. Its the nature of these beasts.
A good carbon cleaning will take at least a 1/2 hr using a metering device that slowly introduces the cleaner into the intake at the very front of the throttle body. I use the purge line port and let it slowly run in so it cleans everything.
AND DON"T USE SEAFOAM I don't care who tells you its this or that, its just not that good. Much better safer products out there.
You are hearing cold carbon knock, as the engine heats up the heads and block grows away from the pistons and it stops knocking. I've had good success using different carbon cleaning products but you may want to try carbon cleaning service from a dealer. The add a bottle to the fuel tank type stuff doesn't work that well and I'll bet your intake manifold is CAKED with carbon. Its the nature of these beasts.
A good carbon cleaning will take at least a 1/2 hr using a metering device that slowly introduces the cleaner into the intake at the very front of the throttle body. I use the purge line port and let it slowly run in so it cleans everything.
AND DON"T USE SEAFOAM I don't care who tells you its this or that, its just not that good. Much better safer products out there.
