Engine dies at 50%+ throttle

[Stbentoak]

Hi @StephenPT I only buy brand name Peak Blue DEF. I heard of others buying cheap WalMart stuff and having issues so I spend the extra $$ to avoid any quality problems. The cam shaft sensor did not sound like something easily replaced. The more they wrench on and take apart the NEW vehicle, the less we want that one back.

That's actually complete horse puckey.... Most all DEF comes from the same bottlers and the same hole in the ground. Wal mart DEF is fresher and identical content as "peak" and they turn it over by the skid loads weekly.
I've seen Peak and other brands sitting on dusty shelves that was over a year old still in the store. If DEF is your issue, it could very well be contaminated, old, or stuff that has turned cloudy. A refractometer would verify this in an instant. A competent tech could rule this in or out in 15 minutes....

 

[steiny93]

What about ? You haven't fixed it in 2 years?

The problem, center console gets so cold you need to put a blanket around it so you can drive it when it's very cold; beverages freeze when in the cup holders. All of this happens at -20F and below, which is common where we live. Only occurs on the diesel '21 we have; the gas '23 Denali and all the pickups '21, '22, '23 in either gas or diesel don't do this.

It's been back to the dealer 8 times; the current 'fix' from GMC is to apply and remove a piece of tape to the underside of the HVAC (based on the outside temperature) unit beneath the center console. The remove the tape as with it installed the wireless charger is unusable in the summer, the phones overheat very quickly because the charger is very warm.

So yah, we've tried to fix it several times, dealer can't do anything, TAC's answer is 'working on it'. But since it only affects '21 Denali diesels in cold climates I'm pretty sure GM doesn't really care.

Doesn't qualify for lemon as it isn't a 'core ability'; so here we sit; all Professional Graded up.

 

[DuraYuk]

The problem, center console gets so cold you need to put a blanket around it so you can drive it when it's very cold; beverages freeze when in the cup holders. All of this happens at -20F and below, which is common where we live. Only occurs on the diesel '21 we have; the gas '23 Denali and all the pickups '21, '22, '23 in either gas or diesel don't do this.

It's been back to the dealer 8 times; the current 'fix' from GMC is to apply and remove a piece of tape to the underside of the HVAC (based on the outside temperature) unit beneath the center console. The remove the tape as with it installed the wireless charger is unusable in the summer, the phones overheat very quickly because the charger is very warm.

So yah, we've tried to fix it several times, dealer can't do anything, TAC's answer is 'working on it'. But since it only affects '21 Denali diesels in cold climates I'm pretty sure GM doesn't really care.

Does qualify for lemon as it isn't a 'core ability'; so here we sit; all Professional Graded up.

That's crazy lol. -20 is cold. Hard to replicate I'd imagine without them keeping your car or having another with similar symptoms.

I'd imagine a infrared thermometer could easily point out where the cold is getting in from.

 

[steiny93]

That's crazy lol. -20 is cold. Hard to replicate I'd imagine without them keeping your car or having another with similar symptoms.

I'd imagine a infrared thermometer could easily point out where the cold is getting in from.

They've had it several times at those temps; the cold breeze through the cabin is very easy to pin point as you can see frost.

 

[DuraYuk]

They've had it several times at those temps; the cold breeze through the cabin is very easy to pin point as you can see frost.

Weird. Hopefully they come up with a resolution.

You would think you could see the cold air stream with an infared thermometer then follow the stream to the point of entry then use the lift to remedy outside/underneath or fix from inside.

 

[GlennSullivan]

Update to this post. Still no diagnosis from the dealership, they nor GMC TAC can figure out the issue. GMC keeps saying they will not do a buyback without a diagnosis. Catch 22.

Friend had a similar problem with his truck, turned out to be the electronics controlling the DEF system.

BTW, GM cannot control the Lemon Law / buyback process. Depending on the state you are in, Lemon Law's are specifically triggered by age and mileage of vehicle tied to the number of days out of service and / or number of times the vehicle has attempted to be fixed and been out of service.

Lookup the specifics for your state and if your situation already meets the parameters, start the process with the state, Screw GM.

 

[dbphillips]

Brand new to the forum here. 2023 Yukon Denali with 3.0 Diesel. Engine completely dies when giving it more than half throttle and throws "Service Emision System See Owners Manual" and "175 mi Until 65 MPH Max Speed". Can reproduce it every single time we try. Started with power cutting in and out rapidly when accelerating, now the engine just dies. Left my wife stranded on the freeway.
The dealership has had it for over a month with still no diagnosis. They have a TAC case open with GMC but still nothing. They have replaced the cam shaft sensor to no avail. Other Googling I've done points to replacing the DEF tank and Sensor. I should mention that this thing has also been guzzling DEF/ 10K miles and has drank over 8 gallons of DEF.
Started the process of a rebuy with GMC but have not heard back. The UAW strike will likely make that more difficult as time passes.
Any ideas or similar threads I may have missed? Thanks in advance!

2023 Yukon Denali
10,000 miles

Did you check OBD codes? Mine was worse as far as random errors and had injector codes. They are pretty sure it's harness related. Dealer won't even guess how long it will take until diesel tech can focus on it, which is fair.

*So, yeah, an injector related harness was worn through at the alternator bracket. I bet all of these odd faults are harness related...

 

[90kpaperweight]

Vehicle still at the dealership. Looks like they will be buying it back. The trouble now is nobody from that department is getting in touch with us. We are in a rental that they way they will pay for but it has been 2 months now. GMC is really dropping the ball on this one. No car and no buyback path as of yet.

 

[DuraYuk]

Vehicle still at the dealership. Looks like they will be buying it back. The trouble now is nobody from that department is getting in touch with us. We are in a rental that they way they will pay for but it has been 2 months now. GMC is really dropping the ball on this one. No car and no buyback path as of yet.

Dang man sorry to hear that. Was hoping for a fix.