when I first got my 96 mustang gt. I would drive and a really loud poping noise would come out. sounded like a shotgun. Then it went away. What could it have been. Bad gas

 

Pinging sounds more like a can of marbles that your shaking....not a shotgun

I see you have a chip....did you accidently put 87 octane in and your tuned for 91 or 93 octane? I bad tank of gas I guess could cause pinging, but it's not too common these days I don't think.

 

so it was backfiring from what your saying?

 

yes it was backfiring and it was before the superchips.

 

Fuel injection back firing? How does that happen?