Sorry for the delay in responding. I have been down for maintenance. It's throwing P050D and P0300. Cold start rough idle and engine misfire. I've changed the plugs and wires, properly seated, dielectric grease, antiseize compound, torqued to 11 ft/lb. Dealer service checked coils and injectors. Will the Xtool check compression or anything else that may be of interest to me?
2017 GMC Sierra 1500
5.3L, 6 spd auto, 71k mi
It's a GM AFM engine which are known for failing lifters and self destructing. Symptoms include jerking, hesitation and misfire.
Indicators in advanced stages would be galling on the lifters, bore, and camshaft lobes.
The matter is in the courts right now.
https://www.classaction.org/gm-lifter-problems-lawsuit
Yours is only 5 years old. If you're lucky, you may still be eligible for a new engine or lifters.
Thanks for the info on the court case. I'm aware, by watching Scotty vid's, of the possible issues with the AFM. That article specifies the Sierra with the V6 engine only. I'll still keep an eye on that.
But if it WERE a lifter issue, wouldn't it be constant? My misfire is intermittent. Just want to understand this fully.
it's intermittent for now
Did some more research on the issue. Yuk. Pretty much a ticking time bomb. I am the second owner but bought a warranty. Have another 2 years and 90k miles on that.
Misfires are covered in the FAQ
Will the Xtool check compression...
It will not check compression.
... or anything else that may be of interest to me?
ignition voltage, Fuel pressure, MAF rate, and fuel trims would be a good start
It's throwing P050D ... Cold start rough idle
Try the troubleshooting here:
https://www.obd-codes.com/p050d
2017 GMC Sierra, 1500, 5.3L, 6 spd auto, 71k mi. (yeah, I've been asking questions lately)
Dealer service department says I MIGHT have a broken lifter of valve spring. Why: P0300 and P050D that they can not find a reason for.
Background: No MIL/CEL, vehicle was acting a little jerky so I put my BlueDriver on it, did not find a code but indicated a random misfire in cyl 6. Put and XTool D8 and same results. Changed plugs and wires and cleared the code. Several drive cycles and no issues.
Took it do the GMC dealer service department for transmission flush and 4x4 service. When I picked it up the MIL/CEL light was on. Took it back in the event they screwed something up. They ran diagnostics on it and found nothing except for the rough idle and codes referenced. Even said that all of my coils, wires, plugs and injectors were working fine. Stated that they put a borescope to look for carbon build up (which I doubt) and found none. Said that it's probably a broken lifter or valve spring. Now a search through TSBs indicate that this is NOT uncommon in these engines, but....Wouldn't a broken lifter or spring have permanent indicators or symptoms?
So I took it home. Cleared out the codes, which it had 13 my the time they got done. I drove it around, smooth as a baby's butt. Got some of the CRC Intake Valve and Turbo Cleaner and ran that through as per the instructions on the can, CRCs video and Scottys video. Still no issues YET. Took it on a good drive, no warning light, put the D8 on it in "Live Data Mode" for misfire data for a good 20 minutes of driving under varying loads. No misfire detected. No "DTC CODE SENT". ETC.
So my question is, if it IS a broken lifter or valve spring, would not the misfire and cold start rough idle be present at ALL times since this is a busted part type mechanical issue?
Sorry for the book. Just trying to be clear.