ok i just dont get it.. i just put another new head on my si..and it still wont start...timing is correct,getting fuel,spark and the compression is fine... what else could it be?!?!?!? a ground,sensor, or bad ecu??? whenever i turn the car to on..the red light blinks once(meaning its on?) list any possible issues please!! EDIT!!not having the o2 sensor hooked up wouldnt cause a no-start would it?