So youve ruled out; the windage tray and dipstick,the trans inspection cover, and the valvecovers and rocker gear.That doesnt leave much. It doesnt sound like bearings.
So that leaves a wrist pin and the flex-plate.
I'm not sure if I've ruled out rocker gear, but I can't feel or hear anything obvious but again I am no mechanic.
How do I check the flex-plate? I've looked for cracks and made sure the bolts are tight. I actually put masking tape on the flex plate where it's closest to the engine to see if it was hitting anything and the tape doesn't get scarred when the motor runs.
What can I do to diagnose a wrist pin? I'm not even sure what a wrist pin does. Is that where the rod connects to the piston? With the engine running I pulled and put back one spark pug at a time to see if the noise would go away and it never did. Should I do a compression check?
I'm going to pull the intake tomorrow and see if I notice anything wrong. Hopefully I see something easy and obvious. Thanks again for the advice