I would be more suspect of the ICM than knock sensors. See if you can get one at a local JY. Check fuel pressure first.

If a knock sensor was bad it would show up on a enahnced scan.

OK, so go to a junk yard and find the piece that all the coil packs bolt into.

Also where can I have an advanced scan performed. I really think that more data would be very helpful, but aside from going to the local auto parts and having them pull the SES codes I do not know what to do? How do i find a local tuning shop?

Thank you guys for helping me.

Where are you located. might have a member near by that can scan it. Otherwise you can pick up a aeroforce scan gauge. You want something that can scan Knock retard. There'* also a android app called torque that I understand now does KR.

I'm in Tampa,Fl.

i think you have to do a custom thing to it get it read KR, i just looked through it and i dont see it

Don't remember where it is, but it'* there.

never mind i figured it out, you have to add the custom gm pids and it will