S Mitch

The scan tool shows' full pressures are good. Both rails. I looked for vacuum leaks and cold not find any. I am starting to lean towards a timing issue.

I did put a larger cam in. I did a full replacement of gaskets and seals.

Looking for advice, just rebuilt my 2000 chevy 5.3l. The idle is rough. I have looked for vacuum leaks and could not find any. I looked at the timing and it is at 8 to 10 degrees. When I put the engine together I lined up the marks on the sprocket as directed, top at 6 'o and bottom at 12'0. I also conducted compression check to make sure for leaking heads and such. My compression was at 125 with no leak off.