Alright so all of the sudden my 00 Explorer (4.0 SOHC) has been running like garbage. It started when one of my cats got plugged (it sure shined a nice cherry red). Since then, I have replaced plugs, plug wires, and coil. They didn't help so I replaced the Crank position sensor now too. The backfiring and what seems to be no torque and little power continues. I actually just had my muffler blow up as well. I am wondering if that became plugged as well. But I am completely lost. Anybody have similar issues or knows how to help?