1994 Chevy Blazer MIsfireing and loss of power.

Electrical problem
1994 Chevy Blazer 6 cyl Four Wheel Drive Automatic

I have a 94 Chevy Blazer that all of a sudden lost power and started to misfire. I Changed the Distributor Cap the Wires and Spark Plugs. It still does the same thing. Someone told me that the fireing order was wack. I checked that also. Still the same. It'll run just backfires and has no power.