I HAVE AN 85 CJ-7 258 I6 STOCK. IT'S MISSING ON 3 & 6 AND I CAN'T FIGURE OUT WHY. REPLACEMENTS:PLUGS, WIRES, CAP, ROTAR, O2 SENSOR, BOTH COMPUTER BOXES, DISTRIBUTER, AND CARB. REBUILT THE MOTAR, CHECKED THE EXHAUST SYSTEM, INTAKE MANIFOLD, EXHAUST MANIFOLD, CHECKED FOR VACUUM LEAKS AND JUST ABOUT ANY THING ELSE I COULD THINK OF AT THE TIME. SOME TIMES IT RUNS GREAT OTHER TIMES IT HAS NO POWER AT ALL. ALL THINGS PREFORMED SUJESTED BY JEEP DEALER AFTER DIAGNOSTIC. THE MOTAR THAT IS IN IT IS NOT THE MOTAR I STARTED WITH FOR THE REBUILD. JUST SWAPED FOR ON ALREADY REBUILT BY A PROFFESIONAL. THIS PROBLEM WAS IN BOTH MOTARS OR OUTSIDE OF BOTH MOTARS. :confused: :confused:

Hmm, have you taken a look at the fuel system? Lines, pump, filter, etc? There may be a partial restriction thats causing your loss of power.

NEW PUMP, NEW FILTER, TANK DROPPED AND CLEANED, AND LINES HAND OVER HANDED.

Geez sounds like a nasty gremlin to me :confused: Does the engine have any computers onboard? If not you've thrown me for one. Sorry I couldnt be more help

did you get the plug wires for theose two cylinders mixed up??They are right next to each other so it is real easy to do..

Also could have a carbon track running between the towers

I bet the CAPSLOCK is stuck in the on position - no, wait, that's on your keyboard. On the jeep, it sounds electrical, if you're sure its always 3 and 6 cylinders. You got new plug wires, had you already done that before you put in the second motor? If they aren't switched then maybe the connections on either end, but that doesn't seem likely if you've also replaced the plugs and cap. Maybe try swapping those wires and plugs with any others that will reach and see if its still the same two cylinders.