DeePa

You can always remove rockers as they are just a torque value if I recall right. When a piston is TDC on compression stroke both valves are closed, so it can be done. Just need to watch both valves.

Any blowby coming out of the dipstick or pcv system?

If the valve is indeed opening and closing like the other cylinders I would think it’s something else. Any way for you to measure lift on the valve? It seems to me that backing off on the preload would cause a worn cam to not open the valve as much. If you pulled the rocker, you could look in at the lifter with a scope or watch how far the pushrod moves. If one is bent, you may not be getting full valve travel. Are you sure injector 5 is firing? Need to rule out that too...broken wire or something ecm related. Did you do a compression test yet? How about a leak down test? That would be my next step before tearing down further. When HP tuners stops counting Misfires, can you pull the plug boot and see if they start happening again?

2017 sierrra. 63k Pads are probably half or less on the front. Rotors are gone and warped. Rears? Fluid is down a bit in the master. Haven’t flushed her yet. Looking for replacements....Chevy brake kit is too much. Any opinions on the best stuff out there?

Do you have window vent visors? The internal channel ones?

Dyno before / after?

24k if you’re lucky old body style. 20k ish annual mileage. Lower trim. Not a crew cab. Not a sought after engine trans combo. none of the stuff you mentioned matters except decent tires. Not perfect condition They don’t hold value dont spend a dime on it. Clean and polish it the best you can.

Gotta look for lash in the drive train somewhere. Could be be internal trans...does it do it in reverse? have you opened up the rear end to look around?

If you disconnect your amp / system, how does the PS respond? any other electronics act up?

Are there any caliper upgrades minus the gmc kit? I can’t find it, but I remember someone looking to upgrade with 2019 up calipers. I need front rotors something fierce. 62k miles...they’re warped badly. Unsure on the rears. I keep putting it off so i can upgrade but the GM kit is $$$$

I always thought flashing CEL means pull over and stop to prevent engine damage.

I’d be looking at bent control arms and checking out the upper strut mount. That wheel looks like it’s a solid few inches off center.

There’s your issue. That shit caused a blemish on my panel on my 14.

Move it away from the belt. Id replace the tensioner pulley too.

It’s basically a free fix. Yes the wheels, caliper, and rotor have to come off. Look it up on you tube. Going to cost more in your insurance premiums when you rear end someone.