on my way to work I was coming down the off ramp from the freeway and my car backfired out the exhaust very hard. After leaving work the car is idleing around 600rpm and is kind of spitting and sputtering. whats really weird is if i 1/4 throttle through lets say 2nd gear, its drives okay until about 4k and loses power and spits and pops but if i get on it, it runs ok? if i rev the car it brakes up real bad after 3k rpm or so...im comfused what happened? 1997 civic lx, d16z6 swap still obd2 running a p2e ecu...? any suggestion are greatly appreciated!!!

 

First thing I would check is timing.

Have you washed the engine bay/engine recently? 94

 

no i haven't washed the engine bay...maybe timing did jump? it happened very suddenly...

 

any cel's? sounds like a bad map sensor

what is it with people claiming maybe timing jumped? has anybody on here ever tried driving a sohc with the tbelt off 1 tooth? it doesnt run.

 

Your fuel is not burning in the combustion chamber like it should, and then it exits into your hot exhaust and internally explodes causing backfires. You are getting weak or no spark at times. Check spark plugs and wires, then check distrubutor.