koumiss45

When I powershift my 1996 GT it seems to backfire once in a while... even more before I replaced the plugs. Am I running way to lean, or what is the deal? The last plugs I changed were when I got it, about 4000 miles ago( those looked to be the original ones). They were pretty burnt up, and the electrodes were almost gone.

redstanger

check o2 sensors and new fuel filter maybe.

rbstang

what kind of exhaust do you have?

Sick96Stang

When I still had all NPI stuff CAI, O/R H-pipe, catback my car would backfire as well when speed shifting. When I got a tune it went away. Hope that helps.

koumiss45

Exhaust, hmmm..... thats not a hot topic around my car. Lets see, I'll start by saying that I am a poor kid who likes his mustangs. Sometimes the money is not there to do it the "right" way, but I get done what I can. I have ( that I built, so be easy with the critisism) a 3" no cat from the headers back with a custom ( ie. homemade) h-pipe necked down into 2.5"(for backpressure bc no cats) mil eliminaters and flowmaster 40's with turndowns( again homemade). Everyone I know loves the sound, thank god. Even some of the SLP guys have told me how they like it. Personally I wish it was toned down just a bit, the police seem to notice it alot, and by alot I mean every other day.

70 MACH I

Backfires through the exhaust indicate a rich mixture, or timing issue. Check your 02's.


John