Backfiring 95 Cavalier

My Cavalier: 5 speed standard will backfire only when I accelerate hard - stomp on the gas.



It idles fine now but on occasion, it will miss every 30-40 second. Other than that it’s fine.



Other than that, it runs fine.



What I’ve done so far:

Re-gapped the plugs.

Changed the wires.

The injectors sound fine



I tried to change the fuel filter but the GM quick connect is now a permanent connect - I couldn’t get the thing off no matter what I did.



Any ideas?

The check engine light isn’t on and I made sure all the vacuum connections were fine - the one from the EVAP can to the back of the intake manifold needed some new hoses, but other than that, they were all fine.