ls-t del sol

Just recently, I have been noticing detonation at part throttle ONLY, at 3k- 4k rpm...sounds like a loose valvetrain bolt, but its prob detonation

i have checked the plugs, they look ok...black towards the base and the nose/tip is whitish/brown.

Setup--

b18b, t3/60-1, uberteg chip, dsm 450's

i get no detonation under full throttle, and the timing is stock with 1 deg of retard per psi

Im thinking/hoping it is a fuel filter, or possibly injectors...the uberteg runs extremely rich so i dont think its because of lean conditions

Any other ideas??

LS_REX

Could be a bad O2 sensor. I had one go bad before I was boosted...It never threw a code but was still bad enough to give me a killer hesitation (way lean) at part throttle when warm.

Rob