Sick 5.3

[GhostWriter]

A couple of months ago, just before surgery, I noticed my LC9 was down on power. Then, I noticed a squeak, squeak, squeak sound coming from the engine.

 

Figured it was from one of the accessories, but the sound remained after taking off the serpentine belts. For some reason, I have a difficult time localizing noises on aluminum engines.

 

A mechanic said it was probably the cam going bad. Took a look at the fuel trims, & there was a sizeable discrepancy between the two banks. Don't remember the numbers. Decided to park the vehicle, till I felt better.

 

Today, performed a compression test. The AFM 4 & 6 cylinders were on the low side. The rest were normal; but, "all" the plugs looked like they were running a bit lean.

 

Popped the valve covers, & turned engine over by hand. Rocker arms moved normally, to the naked eye. Springs looked OK. Removed arms & push rods. No evidence of unusual wear.

 

No codes were thrown. Any ideas?

 

Thanks for your help!

[newdude]

Time for some engine surgery. Heads off, check the AFM lifters out and the cam lobes. We had a 6.0 in with a squeak. Lifter spun in the bore and destroyed the cam lobe it was on. Sounded like an accessory drive chirp.

[GhostWriter]

OK, thanks!