Hello... I have a 2001 Chevy Suburban with about 160,000 miles. The other day I noticed an engine knock and had my wife take the burb to our mechanic. He thought it was the belt tensioner but after replacing it the knocking sound was still there. he than removed the belt and ran the engine and it still knocked. It doesn't appear to robbing power but it does get louder as you accelerate the car. Could it be the timing chain? I would think this motor would get more than 160K before grenading. It does burn some coolant not much though. I also noticed the "service engine" light coming so I'll check to if he downloaded any codes. Thanks in advance for your help!

 

Knocks are usually bearing related. Have you had since new?

 

I had the same problem in my 01 Tahoe it was a loose rod.

 

If your oil is even slightly milky then its most likely bearing wear causing the knocking....a connection rod cap would make more of a clicking or tapping sound..knocking is something bigger moving around....

 

I would check the lifters.if its a tink tink tink sound.and if it gets faster when you give it gas.