2002 Ram 2500 Quad Cab 4x4 with Cummins. 2021 Jeep Grand Cherokee L Altitude
Antifreeze level staying constant?So, the past week about i have been having an issue with code p0302 (cylinder 2 missfire), currently got 298k on the clock. Had p0304, p0306, and p0302 and ran a little rough and a bit shakey, checked the sparkplugs and they where pretty worn for 20k ish on them, replaced them and it resolved the other missfires and the missfire counter's where at 0, ran fine, very slight vibration but its always been that way, check engine light came on for p0302 though engine was running smooth and had no power loss, missfire counters for cyl 2 where counting up pretty quickly (as if it was a dead miss), unplugged the coil and no change in engine tone, swapped the ignition coil over too another cylinder and the "missfire" "went away" and came back 100mi later same code, swapped an injector from another cylinder and no change, it only starts counting missfires for cylinder 2 at idle if above 1500rpms ish it says no missfire and the counter stops. I unplug another coil and the engine shakes like it normally does when there is a missfire, engine runs great, good gas mileage. I ended up pulling the passenger side valve cover checking for a knocked off rocker arm and no issues there, valves actuate and close fully, did a compression test 2 weeks ago just for a check up on it and every cylinder was around 140psi (cold). The weird thing is, when ever there is a true missfire it should shake a fair bit and it isn't. Any thoughts? I'm stumped.