2012 Ram 1500 5.7 misfire

[Eugene Greathouse]

Hey all new to the forum, however been lurking trying to find some information. 2012 Ram Express 1500 5.7 17X,*** on the odometer. New to me but decent maintenance history on it nothing major. When I purchased had an engine code for misfire on #3 and #6. Replaced all coil packs, got rid of the codes, however #6 popped back up after a few days. I didn’t change the plugs when I done the coil packs, I know I should have lol. Changed plugs, #6 came back after a few days. It does have “the hemi tick” however it’s on startup and doesn’t change in tone can’t tell if it gets quieter while driving can’t hear it over exhaust in cab. While I was messing with the plugs and whatnot I did find my passenger side exhaust heat shield is very loose, indicating broken manifold bolts. My question is with the manifold bolts broke would a leak in that be able to cause the misfire on #6? I should add when under throttle and all that truck runs fine, can’t tell it misfires at all. Thanks!

Check your injectors I chased same thing finally pulled injector on # 6 and it was clogged replaced it and issue gone

 

[bfry10]

I'm new to forum Aldo. How about lifter failure and or eco sensor. I believe if sensor malfunctions you will get misfire. Can't remember which cylinder positions are affected by ECO system

 

[EdGs]

Wonder what the solution was to the OP's issue.

 

[Gator Whiskers]

I'm new to forum Aldo. How about lifter failure and or eco sensor. I believe if sensor malfunctions you will get misfire. Can't remember which cylinder positions are affected by ECO system

1,4,6, and 7 are the cylinders that are deactivated by the MDS system while cruising. They are usually the most common lifters to fail, and unfortunately a missfire usually means a cam lobe has been rounded off by the failed lifter