At idle it does it, then gets quiet for about 5 seconds then does it again. When it gets rolling, and I am on the gas, it doesn't do it anymore. If I drive it for about 45-an hour straight, it doesn't make a sound at idle.

I am thinking it is my crank pulley because it is a little wobbly right now. Going to replace them with JET pulleys, but I want some input from you guys on what you think it MIGHT be besides my crank pulley.

It is not a rod knocking or a lifter tapping.I varified that

 

you sure it's not the infamous LSx tapping noise....
every LSx Engine has some form of doing it....

 

did you check the belt tensioner? or remove the belt and see if the noise goes away.

 

Thats the first thing I changed. Then harmonic balancer. It stoped for like 2 weeks after the new balancer. Maybe the old bad balancer did damage on the crank pulley???

 

dumb question but did you check the bolts to make sure they are tight? hard for a balancer to damage a crank pulley. but bad balancers do happen. was it new?

 

Yep brand new Dorman. Put on by a local tire shop threads and care.

3 bolts are tight as I know, I checked them on my lunch break Sunday. didn't check the main one, and the bolt farthest right.

Also, it falls on its face when its cold. Feels like a force of gravity is pulling me back. BUT when it gets warm it runs good. perk up the tires from 20 MPH.

 

after putting a little more thought into it you may want to check your convertor bolts. also what exhaust do you have. does the noise go away when you remove the belt?

 

How do I check converter bolts? My exhaust set up is stock pipe with a cutout, and a magnaflow.

 

you have to pull the dust shield off the bottom of the tranny. if its a 1 piece bellhousing then you have to get them through the starter hole. could also be a cracked flexplate. all guesses since i haven't heard it yet.

 

If it's the flexplate, wouldn't it be making the noise all the time?