Mechanics

CHEVY KNOCKING SOUND FROM ENGINE

1997 Chevrolet Silverado

Engine Mechanical problem
1997 Chevy Silverado V8 Two Wheel Drive Automatic 106, 58 miles

I notice just today when I cjecked under the hood as the engine was running there was a light to medium knocking sound comming from number six clylinder. It sounds like piston slap are maybe a rod bearing. This truck was bought new and I baby this engine with regular oil changes. Can someone give me some clue to this problem?

Thanks

Dan
Avatar
Dan Greif
March 2, 2010.



Hi there,

First check the engine oil pressure with a mechanical gauge, if this is all ok, you can try and prove which cylinder is affected my listing carefully and removing the injector plug, this will shut down the cyl and reduce internal pressure, if the knock decreases you will have found the cyl, if piston slap is the problem you should be getting a poor result with a leak down test on the suspect cyl, check these first.

Mark (mhpautos)

Mhpautos
Mar 2, 2010.
Need some additional information before I can give you an accurate answer.

For example, does the nock begin at a cold start and go away after a few minutes?

It could be almost anything. I do know however from personal experience that Silverados have issues with lifters.

It sounds like you have a single hydraulic lifter that is not filling with oil. The resulting sound is a fast knock.

Send me a PM with the details.

Tiny
Flyboy165
Mar 9, 2010.