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My 1999 Chevy pick up makes a knocking noise when I crank it up in the morning. It has a 5.3 L engine and I have heard this is a common problem. My mechanic thinks the engine may need to be replaced. I listened to your radio show every Saturday morning for the past 5 years and I have never heard anyone ask this question.

I don’t think you have a serious engine problem at all! General Motors has seen this problem and recommend that you have the carbon “dissolved” from your engine! The noise is “ hard carbon” on top of the pistons “banging” against the cylinder head when it first starts up! I know it sounds bad, so you should find a shop that can “dissolve” the carbon from your engine. Using chemicals designed to soften and dissolve the carbon. Once the carbon is removed you can keep it from coming back by adding a gasoline detergent additive to your fuel on a regular basis. Or better yet buy fuel with detergent in it.


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