Hi everyone! I'm at the tail end of the engine rebuild process with the 4.0 back in my 91 jeep cherokee XJ and I've run into a bit of a misfire problem. I managed to break the cam in, but not without an intermittent misfire above 2000 rpm. It idles fine without any misfires and has good oil pressure but as soon as i rev it, it starts to misfire. I've been battling it since, just trying to get it running right. I've replaced the ignition coil and CPS and looked at the forums to see if I could find my same problem, but I just haven't quite found the solution. Any help would be greatly appreciated. I've included a video as reference. Thanks!

 

Check your cap and rotor. I had my rotor come apart on me and cause all sorts of running weirdness.

 

Cap and rotor are brand new, but I'll double check them.

 

Are you sure it's a mis? Doesn't sound like a misfire, which would be more of an irregular rpm
Yours seems to be more than that, almost like an intermittent brief loss or reduction of power.