i just got my obd1 p72 ran all the vtec lines and there are two peoblems. i dont bnelieve vtec it engaging also i cant get my timing advanced enough. i checked the cam gears and they are dead on. is there aneyway my knock sensor is showing knock and retarding my rtiming and not letting vtec ingage

 

bump

 

IAB engages at 6000 rpm, so maybe it is not functioning. By not functioning, I mean the intake runners do not switch, from the long to the short. Check to see that the IAB diaphragm moves when you go above 6000 rpm. You can do this by having some one rev the engine above 6 and you watch to see if the little plunger coming out of the gold piece on the driver side of the IM moves. If there is no movement than there is your problem.

gl