i have 1997 blazer 4.3 2wd. i have a random cylinder misfire according to the machine at autozone. my buddy mechanic cannot figure it out and everywhere else i take it they just want to drop a new engine in it. i'm not ready to go that route yet. what could the problem be

*Combining Consecutive Posts*

i have replaced all vaccuum hoses, coil and the computer. cat is bad, but i was told that would have nothing to do with it. plug wires a new.


*EDIT by swartlkk* - Combined consecutive posts. Please use the edit feature to add additional information to your post if another member has yet to reply.

 

i have replaced all vaccuum hoses, coil and the computer. cat is bad, but i was told that would have nothing to do with it. plug wires a new.

 

o2 sensors?

 

If the cat is restricting exhaust flow, it sure can cause a random misfire.

Have you done a full tune up consisting of a replacement distributor cap and rotor as well as the plugs and wires which I assume you have already done?