2018 6.2 Chev gasoline engine failure

[cdlamb]

My son (23) owns a 2018 Chevy with the 6.2 Gasoline engine.

At 144,000 kilometers, or about 90,000 miles it started acting up on his way to work one morning.

Initial testing was showing 1 engine code, misfire in cylinder 1 due to bad air fuel mix.

Apparently the engine is supposed to use premium fuel, but he's been running regular, and it wasn't throwing any engine codes so he thought it was fine. he doesn't drive it aggressively. At .22 c / liter difference (.83 / US gallon) I don't blame him for trying to save a bit on fuel ups.

They said 0 compression on cylinder 1

Going to open the engine at Chev dealer on Tuesday.

Going to see what his options are, if there is only a failed valve or lifter or what happens with these engines.
They use the AFM system to de-rate cylinders for improved fuel economy.

I have never pulled oil analysis.
He always changes his oil every 8000 kilometers

Wondering if there's any point in pulling an oil sample before they tear into it.

With 0 compression its likely got fuel dilution.
its hard to pull a representative sample from the dipstick without running the engine, & hate to start it up and do more damage.

Anyone know if any mods can be done to the engine to make it safe to burn regular fuel?

I am a Ford owner, and don't know much about Chevy issues.
He is ready to buy a Ford, but I tell him they all have problems.

 

[addyguy]

Might be some kind of extended warranty on the AFM system, as they can have problems.
I don’t think the fuel grade has anything to do with it, but buying a top of the line truck with the 6.2 engine, and then trying to save money on gas by purchasing what it says not to use seems penny-wise and pound foolish!

 

[That John dude]

Might be some kind of extended warranty on the AFM system, as they can have problems.
I don’t think the fuel grade has anything to do with it, but buying a top of the line truck with the 6.2 engine, and then trying to save money on gas by purchasing what it says not to use seems penny-wise and pound foolish!

I know as I own a 14 Sierra 6.2, but the fuel door has a sticker that says “premium fuel recommended” not “premium fuel required”.
In the handbook it says “you might lose performance, and if you hear a knock (spark knock) fill up with premium ASAP”

 

[jetman]

Probably cracked/broke the piston because of the regular unleaded.

 

[wpod]

I know as I own a 14 Sierra 6.2, but the fuel door has a stick that says “premium fuel recommended” not “premium fuel required”.
In the handbook it says “you might lose performance, and if you hear a knock (spark knock) fill up with premium ASAP”

View attachment 242791

Recommended does not mean must.

 

[cdlamb]

yeah, would think it would throw a code or give warning if causing engine damage, and only a "recommended" fuel grade. we are pretty flat land in Saskatchewan. He bought the truck used about 4 years ago from his (step)grandfather, and he purchased it new, so we know the trucks history. 90000 miles seems early for engine trouble like this. He only had the basic 100,000 kilometer warranty I believe or about 60000 miles.

What's everyone use for oil in these trucks. I think it requires dexos 2 or 3 oil, and he was using correct grade I believe, with dealer oil changes.

Not sure if oil analysis at this stage could put blame on oil change?

 

[That John dude]

Recommended does not mean must.

That was my point.

 

[JavierH19]

This is purely an afm issue and it doesn't matter what fuel you run. uoa isn't really worth it unless you want to see if there could be cam damage but the lifters need to be removed. When removed you can see if the cam is chewed or not.

 

[GMBoy]

Lifters. Common, we do 1-2 a week. You'll be ok once fixed. Octane of fuel used is not the reason.

 

[Dave Hess]

Lifters. Common, we do 1-2 a week. You'll be ok once fixed. Octane of fuel used is not the reason.

How much repair bill for this job without engine damage ?

 

[That John dude]

How much repair bill for this job without engine damage ?

Out of warranty I think it’s a 10-12 hour job, so a lot of it depends on the shop labor rate.

 

[GMBoy]

How much repair bill for this job without engine damage ?

We charge $2100 for one side and about $5000 for both with Camshaft. GM parts. Dealership is usually 5k for one side only.

 

[GMBoy]

Out of warranty I think it’s a 10-12 hour job, so a lot of it depends on the shop labor rate.

yep 11.1

 

[jetman]

lifter problem is more common.

 

[cdlamb]

We charge $2100 for one side and about $5000 for both with Camshaft. GM parts. Dealership is usually 5k for one side only.

I seen an ad for a drop in for about $8000 CAD. Maybe they aren't completely remanufactured at this price. What is the price tag on a new engine for a 2018? What are the difference between L86, L87 engine?

 

[That John dude]

I seen an ad for a drop in for about $8000 CAD. Maybe they aren't completely remanufactured at this price. What is the price tag on a new engine for a 2018? What are the difference between L86, L87 engine?

L86 is the 2014-2018 6.2 engine which only 4 cylinders can shut down. L87 is the 2019+ which can shut down cylinders in multiple different variations, and not just the same 4 cylinders. That’s the biggest difference.

 

[mattd]

Just be thankful it isn’t L83. Engine out to replace cam.

That being said probably DOD intake lifter failure. Worst case you need a cam too.

 

[Axenolith]

Lifters. Common, we do 1-2 a week. You'll be ok once fixed. Octane of fuel used is not the reason.

Did the source for those get changed? My local mechanic has a Tahoe in that's on its 3rd lifterectomy in about as many months. my 5.3 2011 has over a half million miles on them. My personal hypothesis on them is that a new supplier is making them (or the supply chain got screwed up) and there is a thermal expansion deviation in the metal utilized within the lifter pieces. That seem reasonable?

 

[cdlamb]

L86 is the 2014-2018 6.2 engine which only 4 cylinders can shut down. L87 is the 2019+ which can shut down cylinders in multiple different variations, and not just the same 4 cylinders. That’s the biggest difference.

When the engine disables the engine does it open both intake & exhaust valves so the cylinder isn't building compression?
Could the 0 compression be a mechanical failure of the AFM system, & not an internal engine problem?

 

[Braapdaddy]

AFM .