2021 Chevrolet Silverado 1500: misfire or rough idle

Filed Oct 27, 2026 · Engine · OH

On October 18, 2026, I was driving my 2021 Chevrolet Silverado 1500 with the 5.3L V8 engine at highway speeds with my wife and two young daughters in the vehicle when the engine suddenly lost power and the truck began shaking violently. The check engine light flashed, and "Service ESC" and "Service Parking Brake" warnings appeared on the dashboard. The sudden loss of power at highway speeds created a serious safety risk to my family and surrounding motorists. I was able to get the vehicle off the highway safely. Restarting the truck did not resolve the issue, and it was no longer drivable. The truck was towed by a AAA contractor to a Chevrolet dealership. Following inspection, the dealership verbally diagnosed a broken camshaft and advised that the entire engine required replacement. The truck had approximately 98,000 miles at the time. A written diagnosis has been requested, and the vehicle is currently at the dealership. The truck has a documented history of engine problems. In July 2023, at approximately 33,500 miles, a Chevrolet dealership diagnosed code P0300 and documented misfires on cylinders 1, 3, and 7. Warranty diagnostic and repair work was performed. Another check engine light concern was documented in November 2024 at approximately 62,300 miles. In April 2025, at approximately 69,600 miles, Chevrolet again investigated a P0300 multiple-cylinder misfire condition. Beginning around 75,000 miles, the truck also began displaying recurring low-oil warnings. I added oil whenever these warnings appeared and maintained regular oil changes, supported by service records. Despite these prior engine concerns and dealership visits, the engine suffered a catastrophic failure without an immediate warning before reaching 100,000 miles. I am concerned about the potential for sudden engine failure and loss of propulsion at highway speeds and believe this warrants a safety investigation.

Filed Sep 17, 2026 · Electrical, Engine · PA

2021 silverado engine failure. Yes it was inspected by a dealership and my extended warranty company and serviced by the dealership. Back on August 5th I experienced a misfire cylinder 3 and felt loss of power. On August 7th the dealership diagnosed both camshafts, 1 lifter, 1 valve, and 1 fuel injector was damaged and never received at warning lights or messages on the dashboard. I was without the vehicle for 39 days and within 10 hrs after picking up the truck i got an engine light on and several new codes on it and can not be driven and being towed. I feel these engines need a recall as it is well documented that these engines go between 60 and 80,000 miles and some a lot less than that, mine has 70,800 and went and now being towed with in less than 24 hrs after engine repair. I will be in contact with a lawyer to follow up on this matter.

Filed Aug 26, 2026 · Engine · TX

I own a 2021 Silverado Trail Boss LT with the 6.2L V8. I purchased the vehicle new at Classic Chevrolet in [XXX]. In XXX, it experienced what I can only describe as engine failure. Severe knocking, loss of power, rough idling. I contacted the dealership as it was under warranty (it had approximately 45k miles at the time). They towed the vehicle in and performed repairs. I do not have service records but the repairs totaled approximately 12-15k dollars and involved several engine part replacements. I received the vehicle back after about 2 weeks. I later learned of the factory recall that was issued by GM affecting my truck and took it in for inspection. This XXX5. It was inspected and passed. They did replace the oil to a higher weight oil as recommended. In XXX it experienced the same issues as before. This time while driving on freeway. Sever engine knocking and loss of power. As I was on the way to work, I drove straight to the dealership to drop it off. After inspecting, they determined it warranted a replacement engine under the original recall. They kept the vehicle about 3 weeks and returned back to me in early XXX. It has been driving fine since then, but I am worried the replacement engine may have the same defects as the original engine. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jun 24, 2026 · Engine · WV

Verified customers cpncern of cylinder 3 misfire and low compression. Inspected cylinder 3 sing a borescope and found excessive oil on top of the piston and on the cylinder walls. There are marks from loose carbon debris damaged the cylinder wall. Upon further inspection the oil looks to be coming from the valve seals. Recommend replacement of the long block assembly to correct these conditions. --Cody Glasscock, Ford Lincoln of Morgantown

Filed Jun 21, 2026 · Electrical, Engine · TX

Check engine light flashes when pulling a load and accelerating above 50mph. Check engine light code is PO300 Random multiple misfires. Took it to the shop and there we’re currently no active misfires.

Filed Jun 6, 2026 · Engine · GA

Was on way to trade truck in onb6/6/26 and got a cylinder #7 misfire. Replaced spark plug and wire and moved coil packs around to trace and stayed on #7. Just had recall completed on 9/25/25 and stated that I've heard a rattling noise in engine area. They performed recall and changed to new oil suggested by GM. Dealership said noise was transmission. I told them that was replaced already within last 50k miles under warranty. Drive it for a few days and rattling noise still there. Took back to dealer on 9/30/25 at cost of $200 diagnositc and stated there is a grinding noise under light acceleration like it's metal on metal. Dealer stated that it was the rear seat rattling. There were NO noises in the cab, only coming from outside at driverside motor area. Called GM 10/1/25 to let them know the denial of motor replacement and we wanted 2nd opinion but we would have to pay out of pocket again. On 6/4/26 had to have truck towed to new dealer. New dealer won't make deal on new truck because of this and we have 2 trips already booked and paid for and 1 at end of June. New dealer is putting in service on 6/8/26 to verify cause. I have called GM after making repairs and they said it was between me and the dealer, there is nothing they can do. This is unacceptable! Im fine if they would offset cost and buy a new Chevy truck and we are going to fight to get it made right. This does make us want to change brands even though we've bought 5 Chevys in the last 10 years.

Filed May 22, 2026 · Engine · 12,000 miles · RI

The contact owns a 2021 Chevrolet Silverado. The contact stated that while driving at various speeds, a flashing check engine warning light appeared on the instrument panel. The vehicle was taken to a dealer where the received fault code PO300 which was a general code for a misfire in the engine. The contact brought the vehicle back to the dealer multiple times due to various fault codes; however, the contact was given the same information. The contact then received a "Low Oil, Check Oil", the contact checked the oil and discovered no oil on the engine's dipstick. Due to the failure, the vehicle was towed back to the dealer where they began an oil consumption test. The valves collapsed and the dealer replaced the valve in cylinders 1,3,5, and 7 as well as the spark plugs. Despite the repair, the contact stated that the failure returned almost two months later. The contact continued the oil consumption test and stated that the vehicle was losing 3 quarts of oil each oil change. The manufacturer had been notified of the failure on multiple occasions and had made multiple vehicle buyback requested; the manufacturer denied each buyback request. After his latest phone call with the manufacturer, he was referred to the federal safety agency Hotline to file a complaint. The vehicle was not repaired. The failure mileage was 12,000.

Filed Apr 9, 2026 · Electrical, Engine · TX

I am filing this safety complaint regarding a documented engine wire harness chafing defect in my 2021 Chevrolet Silverado 1500 with the 2.7L L3B Turbo engine. While driving, my truck experienced erratic acceleration, engine throttling to 3,000 RPM without returning to idle after releasing the accelerator, engine misfires, sudden loss of engine power, stalling, and multiple simultaneous warning lights. These conditions created immediate safety and collision risks on public roads. GM issued TSB 21-NA-149 in June 2021 and a second bulletin September 17, 2021, both before my November 2021 purchase, identifying wire harness chafing in the L3B engine caused by a manufacturing error. A wire harness clip was removed during production creating an uncontrolled harness branch that contacts sharp edges on the ECM/TCM bracket, upper control arm, and shock tower during normal engine vibration. This defect was built into the vehicle at the factory and was never disclosed to me at point of sale. The defect manifested after warranty expiration causing cascading failures; wire harness, catalytic converter, and transmission, all within five weeks. Vehicle has been inoperable since January 8, 2026. Defect confirmed by independent mechanic and by Ancira-Winton Chevrolet (authorized GM dealer) in their own repair documentation referencing GM Bulletin 21-NA-149. Dealer documented catalytic converter failure as consequential damage from wire harness repair. GM created Customer Satisfaction Program N192219370 for this exact defect. My VIN was excluded despite experiencing identical symptoms. No safety recall has been issued. Loss of throttle control and stalling at highway speeds represents an imminent collision risk. I request the federal safety agency investigate a formal safety recall for 2019-2023 Silverado 1500 and Sierra 1500 vehicles equipped with the L3B engine.

Filed Feb 2, 2026 · Engine · AZ

6.2L L87 V8 engine experienced catastrophic engine failure do to lifter failure and a cylinder 8 misfire. Causing additional damage to camshaft. The dealership has inspected the vehicle and refuses to acknowledge the problem as there own. I have invoices for the work if I choose to proceed. Incident occurred while driving on the freeway, complete lose of power and control. This engine is known for this exact problem yet I never received a recall.

Filed Jan 21, 2026 · Engine · TX

The vehicle had originally stopped in a moving lane of traffic. It was towed to a dealership and the engine was rebuilt with a remanufactured engine. The engine idled rough and seemed to be misfiring. The check engine light kept coming on. The dealership stated the vehicle was repaired and I picked it up. The engine is worse. It idles rough like before. It is rough while driving and the check engine light continues to come on. I am about to return the vehicle for the third time before it stops in the roadway again.

Filed Jan 9, 2026 · Engine · NV

I have a Chevrolet Silverado 1500 with the 6.2L engine. I received the recall notice about the loss of propulsion due to a crankshaft issue. The safety of myself, family, friends and coworkers who ride with me on an everyday basis were put at risk because of the faulty engine. I brought my truck in for an oil change in August 2025. I had the Team Chevrolet dealership in Las Vegas Nevada do a telescopic inspection to see if my particular engine had the recall issue. It was discovered the engine did have the recall issue and was kept by the dealership for roughly two and a half months. Chevrolet has confirmed this is a major issue and is affecting roughly 600,000 people. There was no sign of the issue before the telescopic inspection but since the engine has been replaced I have now had three separate issues with misfiring cylinders on the new engine. The plugs and wires have been replaced twice and has not resolved the issue. When the misfires have occurred there were error codes, check engine light notification, and engine sputtering. This again has endangered the safety of myself, family members, friends, and coworkers who ride in my truck on a daily basis. This is now going on four months of issues that keep persisting and I am very concerned that both the manufacturer Chevrolet and the Team Chevrolet dealership are not taking the proper steps in order to solve this very serious issue.

Filed Dec 17, 2025 · Engine · MN

In January 2024, I experienced an engine failure in my 2021 Silverado with the 6.2 Engine. My VIN was not part of the recall affected VIN units built in 2021-2024, it seems to have been built a few months before the last affected group, In any case, I noticed the engine stumbling, and the check engine light came on. I was able to drive the truck home, and when I went to start it the next day, the check engine light was off, so I drove it, and the engine stumbled the check engine light came back on, so I took it to the dealer. They read the codes, and cylinder 5 was misfiring. When they put a scope in that cylinder, the cylinder walls were scored, and there was oil in the cylinder. At that point the dealer chose to replace the engine with a remanufactured engine with no additional warranty added, or any other remuneration for the inconvenience. They did not share with me any specific reason (Lifters / Camshaft / something else) for the engine failure.