94 cs 3.4 backfiring

OK Here's what is happening, Engine was missing at an idle and also would slow down bad going up any incline on the highway, it backfired and blew out the side of cat-converter, at that time I removed all the crap out of converter and then started back up, it was missing real bad at an idle, I put new plugs in it and when it started seem to start clearing out but then as soon as it would go down to idle it would start backfiring out the exhaust constantly, should I now look at wires or coil packs, or module??? Any help would be thankful.

It's more likely you have an air leak vac hose off, gaskets leaking[intake,injectors] or timming chain has jumped a couple of teeth

3.4 known for timing chain and or belt going bad. it has both.