Need Help misfire after replacing lifter

[MalcDogg]

Ok woke to the engine knocking put the scanner on it misfire cylinder 4
Took the valve cover off found out it the lifter was bad replaced the lifter look at the cam still in good shape put everything back together with new head gasket it started shaking hard misfire cylinder 4 moved the spark plug wires coil and injector cleared the code now I have a random misfire any ideas?

2008 Chevy Tahoe 5.3L

 

[CaptainAmerica1]

Did you replace it with an afm lifter?

 

[MalcDogg]

I replaced it with this one it was for cylinder 4 afm lifters and cylinders
It have a random misfire now change the head gasket on passenger side and intake gaskets

 

[MalcDogg]

Did you replace it with an afm lifter?

 

[MalcDogg]

This is what I got for cylinder 4

 

[MalcDogg]

This is what I got for cylinder 4 a

 

[wsteele]

This is what I got for cylinder 4

That is the right lifter from Melling.

A P0300 is a random/multiple misfire. What that means is more than one cylinder is misfiring, it doesn't necessarily mean they are random in nature.

The scan tool that you are using to see the codes likely will let you see the misfire counts for the various cylinders. Knowing which cylinders are misfiring and if it is say 4 and 6 misfiring (say the two you disturbed the wiring, injectors and coils on) or cylinders from both banks would be really helpful.

 

[BG1988]

I replaced it with this one it was for cylinder 4 afm lifters and cylinders
It have a random misfire now change the head gasket on passenger side and intake gaskets

make sure the spark plug wire did not get damaged sometimes pulling them out breaks them esp old wires or make sure it's pushed in all the way

 

[rockola1971]

Did you forget to plug an ignition coil wire harness back in? Possibly brittle wiring in the harness at a coil(s). Check each coil for spark. Not with your finger!

 

[MalcDogg]

Ok so here’s an update

today I change the fuel injectors I notice the o rings was damaged and some of them was bend at the top so I changed them all I forgot to torque the head bolts so did that as well so
New head gasket
New injectors
New spark plugs
New wires
New intake gaskets
Got some white smoke coming out of tail pipe and now misfire cylinder 4 (pending) is back at idle it’s not as rough anymore drive fine other then the smoking
I’m at wits end at this point I don’t know what else to the harness on cylinder 4 do look bad I guess I can try to replace that but what’s up with the smoke now idk ‍