i have a 1991 sunbird with a 2.0 ohc, 3 spd auto trans ............... it's a rebuilt motor with about 20,000 on since the rebuild.......... 4-5 months ago it developed a ticking sound in the engine. i take full blame for this because i had the car up near 100mph!!! anyway, it still ran fine except for a bit of rough idling when it's cold. HERE'S WHERE THE REAL PROBLEM STARTS.............. left work, drove 2 miles to put gas in it, drove another 10-15 miles and as i'm pulling up to a red light i can feel it idling really rough. i put it in neutral and gave it a little gas and i get 3-4 backfires out from the carb(TBI). it dies!!!!! i manage to get it started enough to get off the road. the pressure was so strong it split the air cleaner lid at the wing nut !!!!!!! i get it home and check for trouble codes and there are none........ i've checked the plugs,wires,cap rotor,and coil.........they're all fine ........... i found a couple rubber vacuum lines cracked...... i can't think that bad vacuum would cause such a severe reaction but i could be wrong...............


please, any and all suggestions would be greatly appreciated!!!!!

thanks for all the help.........

Ok has the original catalytic convertor ever been replaced?IF not if it's blocked up with carbon and the car would back fire like a biotch.Since u have good fuel that's my first thought.Check the timing make sure its on the money.And is the injector in the tbi new or old.IF its not running lean to rich and dumping fuel like a faucet ur need to replace that.Check these items and repost ur results.

vacuum lines off can make it do that if their removed enough or leaking enough to mess around with the timing advance on the carb...


®â€îñg666™

Maybe water in the gas that you had just picked up?



My Sunfire

Check your valve train, a bad valve or sticking open will cause it to backfire through the TBI .