2023 GMC SIERRA 1500 Fuel/propulsion System Problems

Vehicle stalled out, lost power, left me stranded on side of road. No warning, check engine lights or any other inclination prior. Turn out to be fuel pump control module.

ECM - Engine System code P0700 and TCM - Transmission System code U0073. The truck went in to first gear and wouldn't go over 5 MPH on the highway. The dealer is saying it can't be replicated but it's happened multiple times to the vehicle in the past week. The truck was taken to the dealership and inspected but they claim nothing is wrong. The check engine light came on as well as the aforementioned codes.

While stopped at traffic signal, vehicle suddenly stops running. Restarted vehicle and had to feather the throttle to keep it running. Engine began to run normally so I continued driving. When I reached approximately 35 mph, a loud rattling noise started and experienced a severe loss of power. Fortunately I was able to safely get out of the traffic lanes to the side of the roadway. I inspected the vehicle, no oil leaks, no coolant or transmission leaks. No warning indicators on the dash. Oil pressure normal. Temperature normal. I limped the vehicle home to be towed to dealer. Approximately 2 months ago this vehicle passed the recall inspection and had the recommended oil change. There was a previous warranty repair performed on a stuck exhaust valve in the #8 cylinder. The vehicle was also brought in to the dealer for suddenly cutting off while driving approximately 50 mph. Again I was able to pull off safely. The vehicle then started normally and I proceeded to drive. The dealer inspected the vehicle and could not replicate the issue, and found no electrical or mechanical trouble codes. There were absolutely no warning indications prior to each of these events.

The vehicle has suffered repeated systemic electrical failures all while being under 8,000 miles. What component/system failed? Power distribution/fuse block, starter, fuel pump control module, horn circuit, body control module, instrument cluster, and charging system. Error codes documented include P0627 (Fuel Pump Control Circuit), U0100 (Lost Comm ECM/PCM), B1325 (Control Module Power Low), U0140 (Lost Comm BCM), and B1000 (ECM fault). All repairs are documented by the dealer, and the truck remains available for inspection. How was safety at risk? The truck lost propulsion at speed, emitted smoke from the engine bay, and became disabled in traffic, placing my family, including my toddler, in immediate danger of collision and fire. Electrical defects also disabled horn and instrument cluster, removing critical warning and signaling functions. These electrical issues have been ongoing for months and GM refuses to replace and can't seem to fix it. Has it been confirmed? Yes. Each failure was diagnosed and confirmed by an authorized GM dealer. Components replaced include fuse block, starter, fuel system computer, horn assembly, and cluster. Despite repairs, issues recur. Inspected by others? GM corporate case managers are aware and have acknowledged defects, though they have refused to issue written determinations. Insurance has not yet been involved, but records are available. The dealer has attempted to repaid more than 4 times with no success. Warning lamps/messages? Yes. Prior to and during failures, vehicle displayed repeated “Service Electrical System,” “Low Voltage,” and communication fault codes. Cluster intermittently blacked out. Smoke in engine bay indicated immediate fire hazard. Cumulative out-of-service days exceeding 20. The failures pose unacceptable risk of fire, sudden propulsion loss, and loss of critical safety functions. I have ALL calls with GM recorded and transcribed as I am in SC (single party recording state) and can provide those.

To All Concerned, I scheduled my vehicle for routine maintenance, but more importantly, I scheduled my check engine light indicator logo to be activated. Following the maintenance and testing of my engine, the dealership informed me that my vehicle passed. For that matter, they put me right back on the road for the check engine light to come on the following morning, and it's still on and off as it pleases. During these very dangerous and extreme manmade and natural disasters GMC seems to think I will have peace of mind because they added an additional 5000 miles to the warranty. What good is that gonna do when for: 1. We arent safe… every scenario you can imagine. 2. Can't travel anywhere in confidence in my vehicle, because they hope I don't breakdown. 3. They gamble with my and other safe driver lives trying to save money. Our vehicles are two-ton vessels capable of creating all kinds of mess. 4. I bet if I don't pay GMC coming for their property so expect the same in return. 5. You can't make this right because my vehicle just tg the dealership two days ago. Please get to the bottom of this a save me the time, aggregation, and hassle of someone trying to convince me I'm fine… well Im not. Thank you [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Truck is starting to feel/act different. There is shaking at acceleration and deceleration. Idling is starting to fluctuate more at stop. Hoping to get this in for inspection. Dealer cannot do so with incomplete recall note on the vehicle.

Accelerating on highway and felt like the engine stalled. Coasted to a stop and the engine would not restart. There was no way to get the truck into neutral so it had to be drug onto a flat bed tow truck.

We were lied to by Sandy Sansing Chevrolet in Pensacola Florida. We bought a 2023 GMC 1500 SLT 6.2 liter engine (L87 V8 gas powered engine. We were told that there was nothing wrong with it and it was a previous owner that owned it. When in fact it was sold at auction! There were no problems or issues when in fact they new about serious issues and problems. GMC was able to listen to my issue and recall. And offered no solutions. I have grandchildren and my wife and I are Veterans. I’m [XXX] and my wife and I were both beside ourselves and scared of being in a accident every time we get in. We are both petrified while driving. My local GMC dealership has no remedy! We’re stuck with a truck that and who knows how long it takes for a NEW ENGINE! I cannot finish buying a Travel Trailer and see the country like we had planned! Can somebody please call me as soon as possible please. Thank you, [XXX] . INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On the highway, the engine suddenly stopped working. Everything turned black. While driving, the screen turned back on but the motor did not start again. I pressed the breaks and the start button to turn the engine back on, while still driving on the highway. It turned back on but then stopped again before I had time to pull to the side of the road. I did the same again and got to bring the car to the side of the highway. It started and stopped several times. I got it to run again so I exited the highway. It turned off again once I was off the highway. I got to drive it slowly to the dealer. He said it had never happened (which is untrue, I found out it is a recurring problem on the GM 6.2 liter). I had brought the car for service to the same dealership about a week prior to the incident. At that time, I told the dealer that the motor was making subtle weird noises. They serviced the car and gave it back to me stating that everything was ok and that nothing showed on their computer. When I picked up the car after the shutting off incident, I was told that their system showed prior issues but that nothing needed to be done since it was not detecting any problem at the time of pick up. About a week after I picked up my truck (after the shutting off issue was supposed to have been taken care of), I returned because I was still noticing the noise. While on a test drive with a GM mechanic, the motor suddenly started making very loud clicking and squeaking noises. He told me to stop right away. The manager at the dealership told me I would get a new motor because there was a recuring issue with the GM 6.2l. After a week, he said only some parts would be changed and that GM would not replace the whole motor. I told him I did not feel safe driving the truck and he said GM decides what to replace not me. I read online that the motor and all oil filters, ducts etc need to be replaced to avoid debris and future problems. No warning light ever went on. Terrifying experience.

Driving truck at highway speed and went to pass a group of slower vehicles on my right. I increased speed to 75 mph and the engine stopped and I had no acceleration. Engine would not shift into Neutral and would not restart. I coasted off to an exit ramp and the truck stopped in the middle of it blocking traffic for about an hour. Highway Patrol was on site to help direct traffic through the intersection of the off ramp and side road. We sat for approximately an hour before a tow truck could get us out of the intersection. The truck transmission was locked tight and the tow truck had to put the back wheel on skates to move it. I had to pay $175.00 to this tow truck company to move me approximately 200 yards to a local restaurant where we waited for the GMC provided tow service to arrive. GMC provided tow truck would only tow to nearest dealership which was in Weimer, TX. At the time of failure there was no warning. The truck just shut down making loud wining noises since the transmission was still in gear. This was an extremely stressful event and I was worried that someone was going to strike us at highway speed from the rear. Traffic was heavy that day on [XXX] heading [XXX] towards San Antonio and most left lane speeds were 75-80 mph and bumper to bumper traffic. The GMC Dealer in Weimer was very professional and inspected the engine on Dec 2nd notifying me that is was a total failure and would need to be replaced under warranty. The dealer had a new engine in hand within a few days and the truck was repaired with two weeks. I had a couple other issues with the OnStar system and the wireless after I picked up the truck and drive it home. I returned it to the dealer and proper parts were ordered to replace a bad control module that had failed during the engine failure. It took some additional time on my own after this was replaced to get my OnStar account back up and running correctly. This truck also had "tailgate drop" issues that the dealer fixed. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMAT

When driving leaving my home and about 2 miles in operation the truck lost power. Not realizing quite what was happening looking at the instrument panel I noticed a drop in RPM and speed. There were no other indicators of problems and The check engine light didn't come on. Instinctively i pushed the accelerator down with no response. Now realizing that the truck was having problems I tried to get off the road. The area of malfunction was not a good place to stop and did the best I could, the truck half out of the traffic lane. In trying to restart the truck which turned over but would not restart. I felt it was acting like it ran out of fuel, checking the fuel gage which indicated 3/4 tank. The truck was towed to the dealership. During the intake conversion the employee stated " it's probably the fuel control module " which I thought was odd at the time with no one even looking at the truck. Finally results was the fuel control module. I am thinking back on how the truck abruptly came to the stop that I was not in a center lane of a busy highway. In my research I have noticed that there seems to be an updated part number and replacement for this OEM fuel module. I did order a spare to have just in case this happens again. Few things I find interesting is that the dealer knew what the problem was during intake, had one on the shelf and replaced it and had me going the next day. This incident i surely wouldn't want to happen to my wife, anyone on a busy highway or other unsafe situation that the engine needs to in operation.

Engine stops running due to a known problem with GM's Fuel Pump Control Module. The unexpected shutting off of the engine poses a serious risk to passengers and other vehicles while operation on all roads. There are numerous vehicles in the service centers of all GM dealerships with the exact same failed part. The three month backlog on receiving parts is indicative that GM knows about this problem and has not issued recalls.

Leaking Diesel fuel, Leaking oil from the rear of the transfer case, making a claunking noise at the rear suspension, My safety is at risk for a possible fire and a crash from the Leaking oil. The vehicle was diagnosed with this problems on [XXX] at Caguas Chevrolet & GMC, also called United Collection Auto. parts were ordered on that date but not arrived. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The fuel in the tank is splashing around and makes bump sound when you come to a stop and is worse when the fuel take is full and goes away the lower the tank gets. GMC has a service bulletin out PIT5161J stating this is a normal condition. This is not normal, I have never had any vehicle I have owned have a fuel tank noise let alone have felt a bump that you can feel in the seat. There is obviously something manufactured wrong and needs to be addressed.