My freind just got done installing his B16A2 in his car; it idles fine and car drives fine; he is using a p72 ecu, when it hits vtec, the car kinda chokes/ hesatates like studdering something is holding it back form time to time it feel like it loose gas and then connects and looses gas and connects again- this only happens when we hit vtec other then that the car drives fine, acelleration is good except for when it hits vtec- has anyone had this problem?

 

is it falling out of vtec? did you check the oil?