d15b97civic

hello i need some help i have a 97 civic ex it has the d15b vtec in it with a s20 trans the problem i am having is when i take off from a dead stop and hit vtec in first everything is fine but when u hit seccond i gete what seams like fuel cut off at 5000 rpm untill it slows down a bit then every thing is fine the speedo is jumping now if i unplug the vss on the trans the car will run all the way past 6500 rpm but cant get vtec i have removed and cleaned speed sensor and the plug

the car has the p2p ecu and k&n short ram intak and exhaust