i have a rx7 with a rpm problem when i get into the throtle at high rpms it starts to buck, i changed the plugs check for vac leaks and fuel leaks nothing only happens when i get to 15psi and 5500 rpm and up / microtech and fuel upgrade on my 7. car was running great then all of sudden it started to happen all the time. please help me out i'm going crazy. my fuel presure is dead on the money.