I've got an H22A1 swapped into a CRX. Today while driving the car started to stumble sorta like you turn the key off and back on real fast, and then it would continue through the rpm range with no Vtec. What the hells going on? What should I check first? It is full of oil and up to operating temp when this happens.

 

check your fuel pressure, how are you driving it when it stumbles?

 

Fuel pressure is 30-40 psi. I can be at any throttle position when I go into Vtec, but it does the same thing.

 

Is the stumble at a certain RPM everytime?