my jeep knocks on cylinder 6 when it misfires. when im driving or give it gas it stops missing and stops knocking. if i havent started it in a few days it misfires like hell and sounds like its about to throw the rod out but it never does. it knocks/misses ONLY when its idling more often when its cold than warm also it does it less when i put better quality gas in it. i put a wrench on the crank bolt and rotate it and if i jerk the wrench real quick i can her it make noise still. my rod and main bearings are still relatively new from the rebuild

 

I'd check to make sure that bearing cap is still tight. Sounds like the crank side of the bearing is hitting against the rod side. Not knocking under power might be the extra oil pressure in between them. My 2.5 knocks at idle, but I'm sure it's worn bearings. My oil pressure is around 15 to 20 at idle and upwards of 45 to 50 under power.

 

Hmmm my pressure is between 40 abd 50 when driving abd 20 to 30 at idle I think I might have to check that

 

Just an idea off my head, but it could be. In my line of thinking (which has proved wrong before, just FYI), when you simply turn the crank bolt, no real impact between the bearings. Do that little jerk, and smack! Small knock.

 

Yes ill do some googling first lol

 

Ever find out the issue yet?