i just replaced my spark plug wires cap and rotor, cause my 95 blazer was misfiring but now its worse any ideas please help

 

Did you replace the plugs along with the wires and are you positive the wires are routed correctly and connected tightly along with the distributor cap? Your title says 'back fire', but in the post your refer to 'misfiring'. They are not the same thing and can lead to different diagnoses.

 

You may want to remove the ICM and coil, then take them to your autoparts store to have them tested. When they test them, have them do it 5-10 times in rapid succession to get them up to operating temperature. Most faults are when hot.