2023 GMC Sierra fuel/propulsion system problems

“On [XXX], at around [XXX] my 2023 GMC Sierra 1500 Elevation suddenly lost power while I was driving eastbound on [XXX]. The battery was still running, but the engine lost power and the accelerator did not respond and the truck would not move. I was stranded in the roadway. OnStar emailed me about a critical vehicle issue and reported DTC P129F. Because the truck was stopped in a live lane of traffic, I called 911. Responders blocked part of the road to protect me and to give the tow truck room to recover the vehicle. No one was injured, but this could easily have caused a serious collision. A few days later, I had the truck towed to Seaview GMC in Lynnwood, WA. The dealer diagnosed an internal failure of the fuel pump power control module, the K111 Fuel Pump Driver Control Module mentioned in the GM Bulletin earlier this year. This matches a known issue described in GM Service Bulletin 24-NA-139, which covers DTCs P129F and P023F and lists 2023 Sierra 1500 models. The bulletin describes symptoms including no-start and stalling. The dealership has attempted to charge me $200 for diagnosis and $261 for the fuel pump module. I had asked them if this was covered…”

“On XXX, at approximately 2:30am, about 30 hours after purchase, a 2023 GMC Sierra Denali Ultimate suffered catastrophic engine failure in [XXX] during a planned 20 hour trip. The vehicle had about 49,007 miles at purchase and 49,411 miles at the time of failure. The check engine light appeared during the trip. Over five hours into the journey, shortly after passing through a one-lane construction zone with no shoulder, the truck made noises, then lost driving power and began slowing among highway traffic. The dashboard displayed "LOW OIL PRESSURE STOP ENGINE," code P0016, and a transmission warning. I had to move into another lane to reach the shoulder. The sudden loss of propulsion at 2:30am created a serious crash risk because the truck could have been struck by nearby traffic or become disabled on the one-lane road without a shoulder. The engine had received the GM L87 recall remedy on XXX involving a change to 0W-40 oil. Despite this remedy, the engine failed while the vehicle was moving. The repair order lists replacements for the engine, radiator, oil cooler lines, intake manifold and gaskets, spark plugs and wires, water pump gaskets, high pressure fuel…”

“Addendum to previous submission # 11760415. At 15,033 mileage again multiple codes present along with a rough running engine. Dealership service dept confirmed on 9/17/2026 verification of 10 active codes , 2 pending codes triggering check engine light. Onstar notification as well of engine issue. Prominently codes P0016 & P0340 lead the list. PICO testing was stated to have failed two out of 3 parameters. Officially stated now as an engine defect which is being directed to be replaced with a remanufactured , not new , motor. Very fortunate to not have experienced dramatic failure ( loss of propulsion ) at highway speeds far from home. Even though this vehicle warning's persisted prior to this ultimate conclusion it was insisted that ultimate failure was necessary before any resolution would be instituted. A safety conundrum if you will. A high probability safety risk of continued use ( based on historical data on this known engine failure risk ) to ‘ prove ‘ it would fail like many others already have. A fair assessment of my personal experience.”

“I am reaching out to NHTSA due to a vehicle that I believe will get me and/or my family in a major accident and cause serious injury or death. The vehicle that I had purchased in 07/08/2025 had a clean history report and was bought at 54,587 miles. It started having issues 8,563 miles later (odometer reading 63,150 ) on a trip that was 400 miles round trip. I was driving the vehicle on a highway at 65 mph and i felt a knocking vibration in the pedal it was not long before i could even pull over when the engine throttle had completely lost power causing the vehicle to almost come to a complete stop immediately having to steer onto the shoulder. after failing with no check engine light or warning present during the use of the vehicle on the road. it was giving off high temp/engine overheating with the engine making a continuous knocking sound in the engine. It eventually seized to work completely not being able to shift into neutral to push, and had to get it towed to the dealership 204 miles away. GM had advised the dealership to replace the whole engine which they did, and that second engine had given out 678 miles later (odometer reading 63,828.) I am now on…”

“purge pump failing confirmed at dealership this part has been recalled on same truck but not specifically this vin . I was told I need to report it to you guys so that it could ge added.”

“13 unresolved problem codes relating to hard engine starting,rough engine running,vehicle initiating safe mode operation, upon a highway trip. P0016 engine code detected and Onstar messaged for immediate service. No resolution at dealership , after resetting codes an additional 9 are active / pending at 2nd dealership visit. Abnormal engine operation since , dealership advises a hard failure has to occur before a resolution can be instituted. Similar advice from GMC direct phone call in help line.”