01 Burb 5.3 ~290K P0303 Bad Engine?

[clinebarger]

Back to a Leakdown test then! And if that passes....You can remove both valve springs & replace them (I would check them as I have a valve spring checker)

Valve guide issues are rare on LSx engines, But with @300,000 miles.....Anything's possible.

 

[dogememe]

Originally Posted by clinebarger
Back to a Leakdown test then! And if that passes....You can remove both valve springs & replace them (I would check them as I have a valve spring checker)

Valve guide issues are rare on LSx engines, But with @300,000 miles.....Anything's possible.


Ok I will perform this test and update you. Might take me a week or so

 

[mattd]

Good luck let us know what you find.