Backfire through exhast

[Dubnation762]

I have been fighting my 91 explorer 4x4 4.0. It has almost no power and if I dont unplug a vacuum port it will not idle. When I do unplug it it has throttle but backfires real loud out of exhaust. When I put it in gear it is real sluggish and continues to back fire. Plug wires are wired correct. I've tried other things such as changing mass air flow, tps, iac. With no change. Any help would be awesome I'm so frustrated.

 

[Mbrooks420]

Is the timing correct? What happened to start all this?

 

[domct203]

Is your CEL on?

Any diagnostic codes?

I agree, sounds like a timing issue, I would not drive it any more until it’s figured out.