LandonGiles

I just installed a new cam, lifters, pushrods, oil pump, long tubes, related sensors, CHE trunions, spark plugs, engine mounts and a 3000stall on my 2001 Trans am with the 4l60. When idling the car runs and sounds perfect but once I start driving and the car shifts from 3rd to 4th gear it sounds like a tapping noice. I have checked torque on all rockers and exhaust manifold as it sounds similar to an exhaust leak, and everything seems fine. Along with this I checked knock sensors and harness. Does anyone have any ideas before I send it to a shop to have them diagnose it?

grinder11

iTrader: (1)

I agree with finding an exhaust leak. When an engine is under a greater load an exhaust leak will be exacerbated. You're probably on the right track.....

Che70velle

iTrader: (6)

Detonation can be mistaken for a tick or tap sound. Sounds like car has been tuned already…did tuner turn off knock sensors by chance? Some do unfortunately. Detonation shows up on spark plugs…looks like peppering of sand, like a sandblaster from 30-40 feet away was pointed toward the plugs and only a few particles hit the ground strap. Worth a look. If knock sensors are still turned on, have your tuner ride along with you while watching the tune via HPTuners. IF this is knocking, it will show up. I’ve been involved with a few builds that had this same issue under light load at cruise, sounded like tapping. We pulled a couple degrees of timing in that area of the tune and all was well.

wannafbody

iTrader: (2)

Did you use GM MLS exhaust gaskets? They work well for headers. Headers also amply valvetrain noise.

RaulHiggins

Is everything completely well?

LandonGiles

Yes everything went in well. I have checked just about everything I can next step is I am going to pull my pushrods and check the lengths again. And look at the cylinders for interference. The noise comes and goes. So I’m kinda just checking everything possible.