Hello guys, I am having a misfire on cylinder 5 that I can't seem to get away from at all.

The P0305 code is not making a light on the gauge (it's pending) but I can still scan for it and slightly feel it at idle.

Vehicle: 2014 Chevy Suburban (Vin "0").

What I tried:

• Moving the spark plug to a different cylinder (didn't do anything)
• Moving coil and boot to a different cylinder and replacing said coil/boot (didn't do anything)
• Replacing fuel injector (didn't do anything)
• Compression test (good compression)
• Head gasket leak test (no leak)

Other notes:
I replaced the head gasket some months ago, and one of the top small head bolts snapped due to a faulty torque wrench... I have yet to deal with it as my compression/head gasket are seemingly fine.

Any guidance is appreciated.

 

Image attached shows two plugs; one from cylinder 1 (left, good) and one from cylinder 5 (right, misfire). Do they look alright?

 

Update:

Took the valve cover off and inspected the push rods, something is definitely weird with the cylinder 5 intake push rod. It looks like it has this orange scratchy appearance on the end that is closest to the camshaft. I haven't been able to find anything about this online at all, no idea what this is. Anyone ever seen something like this?

Images push rod order (left to right): Intake 1, exhaust 1, intake 3, exhaust 3, intake 5, exhaust 5.

 

The head bolt that snapped off, was it near #5 cylinder? The orange appearance on the push rod, is it rust? Did you check the lifter?

 

The snapped head bolt is near cylinder 5, yes. The orange stuff has an oil/grimy texture, wipes off easy. Haven't checked the lifters or cam yet.

 

I think you need to replace the broken off head bolt.