2 shops 5 mechanics and a 'star' tech..No clue why misfire
I have a 04 wrangler TJ-Unlimited. 4.0L 6I. 100340 miles
It is throwing misfire in 1 and 2 codes. Jeep and my mechanic can't figure out why it's misfiring...it usually only misfires in idle - but if it does out of idle its at about 55mph. The check engine light is on and last night it started flashing at me repetitive and the truck started running like it did with the failed lifter. I continued to accelerate (figuring either will total it out and i'm done with it or would cause another symptom to help figure it out). It went back to running its "normal" after couple mins. I have been dealing with this for bout 6 weeks now. It ran great for 1k miles after the lifter job...ANY IDEAS WILL BE GREAT!! :
I had a similar problem for the longest time and threw lots of new parts on as well. Rebuilt head, wires, plugs, injectors, cap and rotor. Misfire on cylinders 1 and 6 every time, and it would usually pop when I idled for a little while. It ended up being for me that the bolts on the underside of the intake/exhaust manifold were loose. I traced a slight whistle noise with a stethoscope to the underside of the intake and checked the bolts. They were loose enough to twist by hand. I think they had somehow worked loose over time after the head was replaced. Maybe like when they tell you to re-check the tightness of bolts when you replace suspension components. Worth a try.
Yes cam been checked they said was good not new though.... spark plugs were in before lifter work done truck ran great for thousand miles after lifter work...the heads were resurfaced so the new gasgets would sit right I know they didn't check valves unknown on springs... can't find air leak..
Tension pulley seems loose to me....the bolt on left side closest to firewall on top side the nut is not even touching the tip of valve cover I know certain order of tightening but can I redo that one without all the others? Can't hear air or not due to engine bouncing and loud chug sound