My car has a horrible misfire. It will rev at part throttle but mashit and nothin, then it bucks harshly. If I just start the motor and rev it from the engine bay at part throttle it will run but will miss about every 1 sec or so. I have replaced the cap, wire, rotors and plugs. Just replaced ignitor and coil. It did this after sitting in my lot for a few nights. I know its got to be ignition because it backfires along with the harsh bucking when it misses. Everything is snug and conected, all the ground straps are sound. Any guesses are welcome. I have not touched either the intake or exhuast manifolds. I have checked all the vacuum lines and its not timing I have not touched that either. Thoughts anyone!?!

 

Anyone!

 

yeah my b16a2 swap misfires too when i accelerated it kind of bogs a little then accelerates ,then when i shift or let the gas pedal go ill hear a popping sound in the exhaust.

 

first things first....try adding some fresher fuel

 

Did that 93 octane chevron