ok little lost. bought it for 500 bucks. had the typical failed lifter. owner replaced cam and lifters and couldn't get it to run when put back together. ended up being a bent push rod. now runs and drives put about 3,000 miles on it as it is cause its been sitting for 4 years before i got it. it has a number 8 misfire, thats my issue that wont go away. changed plugs swapped around coils even took coils off my 08 aspen 5.7 to try. No dice still number 8 misfires. moved around injectors same thing. got a noid light to confirm working plug for number 8 injector. the bent push rod was intake for number 8. there are others that are slightly bent aswell going to replace them all. looks like when he put motor back together he didn't get things lined up right with the rockers and bent them. i have a launch x431 scan tool when i watch 02 sensors they all appear to be working correctly based on engine speed and temp. when watching which cyl is misfiring only shows number 8 misfiring and when i bring up the rpm about 2k it stops misfiring. only thing i can think of is i am loosing at a really slow rate, coolant. like i filled it once i got it running and have put just over 3,000 miles on it and it still covers all the cores when you look in the cap. so its just barely low could be air in the system bleeding out finally.

any ideas would be appreciated. i'm just lost, checked all the normal things and some that aren't normal.

thanks in advance.

 

Manually rotate crank till #8 is TDC on compression stroke. Using a spark plug adapter. attach and put compressed air to see if the cylinder holds pressure. (Whatever the air pressure is from ur compressor )
If quick bleed, I'm guessing poss. slightly damaged valve ?? The push rod was bent, correct, then something caused enough force to bend it. Installed cam out of time, the pistons hit the valves, bent some rods, damaged some valves and end of story. It is a Hemi. the lead side of both valves are slightly closer to the piston than reg. engines