GMC Sierra 1500 start-stop problems

Filed Oct 23, 2026 · Electrical, Engine · NE

Three different times now (most recent: 10/22/2026), I have had my truck completely shut off when coming to a stop on the highway/interstate. I always have auto start/stop disabled when I drive. When it happens, a message shows on the dash that says press start button. No other codes or check engine light. Thankfully it has started every time, but this is obviously a serious safety concern. After the second time it happened, I had the dealer (Woodhouse Buick GMC Omaha) look at it on 9/14/2026, but they couldn't find anything since there were no codes. I'm not sure if it is an electrical issue or this is related but my audio will stop working at times as well. Nothing from the radio or any blinker sounds. Sometimes it's static with a high pitch noise. 2026 GMC Sierra Elevation 5.3 EcoTec3 v8 10 speed

Filed Sep 10, 2026 · TX

The engine coolant control valve on my 2021 GMC Sierra 3.0L Duramax diesel failed. This specific component failure triggers an active vehicle 'No-Restart' safety event during automatic engine stop/start operations (per GM Service Bulletin #24-NA-070). This condition can suddenly prevent the vehicle from restarting when stopped at intersections or in active traffic, creating an immediate highway safety hazard and leaving the vehicle stranded. Additionally, the vehicle's radiator cooling fans run continuously at 100% maximum capacity as a system fail-safe, creating severe electrical drain. General Motors has issued a Special Coverage Adjustment (#N252508341) acknowledging the high failure rate of this part, but it is capped at 150,000 miles. Because this defect causes unexpected stalling/no-start safety risks in live traffic past this arbitrary mileage limit, a formal safety recall is required.

Filed Aug 17, 2026 · Engine · GA

The engine shuts off while slowing down. It cuts off cleanly and the entire dash lights up and the transmission shifts to neutral. The driver display says to put the truck in park and hit the start button. After you do this the truck runs fine for about 2k-3k miles and does it again. I has done this 5 times within 10k miles. The dealer says nothing is wrong with the truck because the computer doesn't record any codes. This happens regardless of whether the auto stop/start feature is on or off.

Filed Aug 6, 2026 · Transmission · 2,000 miles · TX

The contact owns a 2026 GMC Sierra 1500. The contact stated that while her husband was driving approximately 10 MPH, the vehicle unexpectedly shut off and independently shifted into park(P). The contact stated that previously, while the vehicle was idling in a parking lot, with air conditioner activated, the Auto START/STOP feature engaged, and the vehicle shut off. The message “Service Transmission” was displayed. The vehicle was taken to a local dealer and was diagnosed with transmission failure. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was approximately 2,000.

Filed Apr 19, 2026 · NV

Safety Complaint – Delayed Acceleration from Automatic Engine Stop/Start I am reporting a safety concern regarding the automatic engine stop/start system in my GMC truck. During normal operation, the system shuts the engine off when the vehicle comes to a complete stop. When I release the brake and press the accelerator, there is a noticeable delay while the engine restarts before power is delivered to the wheels. This creates a hesitation between driver input and vehicle response. This delay presents a safety concern because it affects my ability to react quickly in situations that require immediate acceleration. I have experienced multiple real-world scenarios where this hesitation impacts safe operation: While stopped at an intersection preparing to turn, I observed oncoming traffic approaching faster than expected. When I attempted to accelerate to complete the turn, the delay caused by the engine restart reduced my ability to clear the intersection promptly. In stop-and-go traffic, I needed to move forward quickly to maintain safe spacing or respond to changing traffic conditions. The hesitation before acceleration limited my ability to react immediately. When pulling into traffic from a parking lot or side street, heavy traffic often creates small gaps that require prompt acceleration. Due to the delay in engine restart, it is difficult to accurately gauge and anticipate the truck’s response when pressing the accelerator. With this hesitation, safely merging into traffic in these conditions becomes extremely difficult and, at times, effectively impossible. In situations where a vehicle encroaches into my lane or a hazard develops unexpectedly, the delayed throttle response reduces my ability to maneuver out of the way quickly. This is not simply a convenience issue. The system introduces a delay between driver input and vehicle response, which can reduce reaction time in situations where immediate acceleration is necessary to avoid a potential hazard.

Filed Mar 24, 2026 · Electrical, Engine · 75,000 miles · TX

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 50-65 MPH on an incline, the contact believed that the transmission was slipping or there was a misfire coming from the engine. The contact stated that the vehicle failed to restart automatically after the engine AUTO Start/Stop system was engaged after a complete stop. Additionally, the contact stated that after driving for a while, the vehicle went into LIMP Mode. The check engine warning light and other warning lights were illuminated. The vehicle was taken to the dealer to be diagnosed. The contact related the failure to GM Campaign Number: N252515590 (Corroded Ground Strap); however, the dealer had informed the contact that the vehicle was not covered because the VIN was not included and there was no warranty coverage on the vehicle. The vehicle was not yet diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the federal safety agency Hotline for assistance. The failure mileage was approximately 75,000.

Filed Feb 27, 2026 · Engine, Steering · NV

I stopped at a red light in the middle of a 50 mph intersection when the light turned green The engine completely shut off, and it didn’t want to turn back on. I was stuck in the middle of the intersection in a very high risk area, putting myself and other drivers at risk. OnStar diagnostics didn’t report any issues with the truck. According to their diagnostics, everything should have been running perfectly fine. The motor shut down completely and we weren’t able to shift the truck into neutral in order to try to move out of harms way. There was no warning lights or anything before this happened. The first tow truck driver that came by was told that he was there “in order to do a jumpstart” He ran a diagnostic on both of the batteries and said that they were perfectly fine. Another tow truck had to be dispatched since the first wasn’t equipped to take the truck. In total we were stuck in the middle of the intersection for almost three hours. The amount of times we almost had someone crash into us during that time was very concerning. Dashboard and lights were all working perfectly fine. Auto start stop technology seems to have shut down the motor and was not able to get it to turn back on . This vehicle is a safety hazard.

Filed Feb 25, 2026 · Electrical, Engine · 16,000 miles · TX

The contact owns a 2025 GMC Sierra 1500. The contact stated that while stopped at a traffic light, the gear shifter was shifted to park(P) and the vehicle stalled. The message "START Engine" was displayed. The vehicle was restarted, and the Auto START/STOP feature was disabled by pressing the "A" inside an orange circle. The contact stated that on another occasion while reversing into the driveway, the vehicle stalled. The message "START Engine" was displayed on the screen. The dealer was contacted; however, the vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired and the failure persisted. The manufacturer was not notified of the failure. The failure mileage was approximately 16,000.

Filed Sep 21, 2025 · Driver assistance, Electrical · IA

Every time I pull the truck into my garage or a parking stall at low speeds while using the front park sensor it will shut off with the automatic start stop while still in motion. Then you have to let off the brake pedal for it to start and sometimes the vehicle will search forward.

Filed Aug 4, 2025 · Electrical, Engine · 250 miles · OR

The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving with cruise control mode set at 55 MPH, the vehicle independently accelerated to 98 MPH, and then the vehicle lost motive power. Additionally, the contact stated that the vehicle had failed to turn off upon pressing the Engine Start/Stop button. No warning light was illuminated. The vehicle was able to restart and was taken to a local dealer to be diagnosed, but the cause of the failure could not be determined. Additionally, the contact noticed that water was leaking inside the vehicle through the rear window on rainy days. The contact stated that the infotainment screen had failed to turn on as intended on some occasions, and the screen had displayed a rearview camera image while the vehicle was in drive(D) on other occasions. The contact stated that while driving at various speeds, the transmission made an abnormal sound, and the RPMs failed to decrease as intended, but suddenly dropped while decelerating. Additionally, the contact stated that the headlights, the fuel pump, and the main pulley were replaced at the local dealer. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the federal safety agency Hotline for assistance. The failure mileage was approximately 250.