96GTMustang

Why is my car back firing when it idles and when i downshift or take my foot off the gas?? Could i be running too rich? Could something be wrong with my o2 sensors? I have stock fuel injectors with all my mods..help!!!!

NORMAN99

My car backfires all the time that's because i have no cats. Besides Ilike the backfire sound when i down shift to make a tight turn. I might have something to do with your fuel air mixture.When did itstart doing this?

96GTMustang

when i took it out of the garage the other day..its been sitting for a couple months. I did an oil change and now it back fires

NORMAN99

Might want to try to add some engine treatment in your fuel tank. Im not sure if that will do the trick or not. When it comes to motor issues im kinda weak in that department. Im trying to learn motors myself.[][]

04mineralgreyGT

Is it a loud bang like a gunshot (backfire)? The gas could be stale from sitting for so long. How much gas is left in the tank. Fill it with some 93 and some engine treatment to clean your fuel system out.

ripper

Is it backfiring out the intake or out the exhaust?

Hash06

is your CEL on, you are probably running really rich. i guess you have a dyno tune for your mods. what was your a/f ratio?