2015 GMC Sierra 1500: misfire or rough idle

Filed Mar 8, 2026 · Engine · ID

Another GM truck AFM failing. It failed at 70,000 miles causing P0307 cylinder 7 misfire. No aggressive driving just commuting to work. Truck just got done with a new oil change. It's another to add to the hundreds/thousands seen on Reddit threads of all 5.3/6.2 AFM/DFM that this organization turns a blind eye to.

Filed Apr 30, 2025 · Engine · PA

With all the GM engine problems being recalled, the known issue witht he AFM/DOD on all the models 2013 and up on 5.3L and 6.2L engines should have been recalled. The valves are known to collapse and nending push rods, causing damage to the cam shaft. This can cause ht eengine not to run. The symptoms and possible icidents include the same as the current recall the federal safety agency Campaign Number: 25V274000. My engine has been repaired twice now due to this AFM/DOD issue. I have all the paperwork from GM dealer that repaired it. I will upload the first repair, I need to scan the second repair. The engine is now making the ticking valve sound ans the vehicle is services regularly. What component or system failed or malfunctioned, and is it available for inspection upon request? AFM/DOD valves collapse causing enegine damage. How was your safety or the safety of others put at risk? Lack of power while driving, loud engine knock Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, by the dealer Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Insepcted by the dealer, and only the damaged parts replaced, not all the valves that can still collapse. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No warning, engine light came on due to misfire on both incidents.

Filed Feb 5, 2025 · Engine · ID

Purchased this vehicle on 06/29/2023 from Robideaux Motors in Coeur d Alene ID. with 81,397 mile on the odometer. On 01/05/2024 the 6.2L engine with 84,109 miles, started having a ticking sound after starting it at my son's house two miles from home. I called the dealer and was told to bring it in for diagnosis by a tech. While driving the truck to the dealer the ticking got worse and motor started to shudder and the check engine light came on. Cause was a misfire on cylinder 4 due to bent push rod and failed lifter. Replaced lifter bank 2 with new push rod. Total cost was $2,852.74 (have invoice). After many calls and letters to my extended warranty company, they finally paid $1688.54 of the total cost. On 08/29/2024 the same ticking sound started again as well as the shudder and check engine light. I had it towed back to Robideaux Motors and was told it was a misfire on cylinder 6 due to lifter failure. Robideaux Motors did repair under their repair warranty. I know that this vehicle is not included in class action suit, due to the year. I feel this to be a continuing problem with the GM 6.2 and 5.3L motors encompassing many model years. Just wanted to document that the number of years covered in the law suit should be expanded.

Filed Aug 1, 2022 · Engine · MA

The issues started when I began to notice that I was not having a constant flow of heat coming out of the vents inside of the vehicle. I brought the vehicle over to a local service center and the mechanic there discovered that my antifreeze reservoir was completely empty, but I did not have a leak. After filling the truck back up with coolant, a few days later, while driving, suddenly the truck began to run rough as if the vehicle went into "limp mode". I noticed that the check engine light was flashing and the traction control light was on. At stops, the truck would rough idle, shake, and there was a large amount of smoke coming from the tailpipe. I was able to get the truck back to the same service center that ran some diagnostic tests. He told me that there is a fault in the number 7 cylinder which has no compression in it. I had the truck towed to a local GMC dealership who confirmed that there was no compression in the number 7 cylinder and said that there was a lifter issue in the engine requiring an expensive fix. GMC had the truck from the Friday after Thanksgiving (the Year 2021) to January 4, 2022, to make the repairs. Repairs were delayed due to the dealership not being able to get the necessary parts in a timely manner.

Filed Nov 1, 2021 · MI

transmission. just like others with this year and mine went out .i was going like 50-55mph and i almost got into a accident while my son was with me . truck started sputtering and shifting up and down check engine light, stabilitrack, and something else, my truck seemed like it was down shifting and not going into gear, rpms were going from 1000 to 2000 and truck was shaking and started making a howling noise. it felt like i had a misfire in a way. its available for inspection, i

Filed Aug 27, 2019 · Brakes, Engine · 59,000 miles · CA

Tl* the contact owns a 2015 gmc sierra. While driving low speeds, the vehicle violently vibrated and made an abnormal noise. Also, the stabilitrak and check engine indicators illuminated. The contact mentioned that the check engine indicator periodically illuminated and flashed. Also, while driving, extra force was needed to depress the brake pedal and stop the vehicle. The vehicle was taken to boulevard buick gmc (2800 cherry ave, signal hill, ca 90755, (562) 492-1000) where the contact was informed that the vehicle misfired and the entire engine needed to be diagnosed. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 59,000.

Filed Oct 15, 2017 · Fuel system · 10,000 miles · TX

When accelerating at a very slow speed the engine seems to misfire or sputter and then the engine increases RPM and the truck accelerates as expected. Overall the engine lacks power and there is loud clicking sound that originates from the engine compartment area. I spoke with service manager at gmc and I was told that clicking sound was normal and gmc was working on the acceleration problem.