93 2.3L backfireing and cackeling

[sibert3s]

Ive been getting a big back fire every time is shift 1to2 and 2to3 and it cackels when i coast down hills or rev the motor up and let it come back down.

I love the sound but what does it mean, is it running to rich and what is it doing to my mpg?

 

[Ric]

Sounds like it's rich and combusting the unburnt fuel. My guess is you have a hole in your exhaust somewhere too.
Check from teh MAF all the way back to the throttle body to ensure you dont have a leak/loose connection. Check the PCV as well.
My turbo car blows fire balls between hard shifts at certain instances as my blow off releases the metered air. The car even exploded it's muffler once when I had an injector stuck open.