Originally Posted by
four_by_nut
Is this happening when in the boost at 6500rpm but not when out of boost? If it's happening in boost but not out of boost I have the following thoughts. If it happening not in boost...then ignore the following.
Not sure if you have swapped injectors or not, but keep in mind, at higher RPMs there is less time the injector can pulse to inject fuel. While it might be able to keep up and lower RPMs, those higher rpms leave very little time for injection. Perhaps a larger injector is needed? Take a look at your injector pulse time (INJ B1 or INJ B2) in your scanner. Take 6500 rev/min multiply by 1min/60s and then invert it to get sec/rev => 0.009sec/rev. Then multiply that by 2 because the came spins half the speed of the crank. So that's only 18ms for the injector to be able to inject all it needs to at that rpm. At lower rpms (let's say 3250rpm) you have 36ms for injection and most stock injectors can probably handle that. If your INJ B1 or INJ B2 are trying to inject longer than the valve it open, then your injector is not large enough. I ran into this when I turbo'd my little ecotec motor. Injectors were maxing out before I got above 5k with boost. Went from 45# to 60# injectors and it solved the issue. Just a thought.....