2022 MERCEDES-BENZ Glc 300

Defect Summary: Since 2024, my 2022 Mercedes-Benz GLC300 has had a persistent, abnormal engine noise consistent with the sound of a 4-cylinder diesel engine, despite being gasoline-powered. The noise occurs both while idling and in motion. On several occasions, the coolant warning light illuminated while the noise persisted. The defect has worsened over time, becoming louder and more frequent. Events & Safety Risks: The dealership repeatedly claimed “no problem found” because no warning lights appeared and no scanner codes were present, ignoring my time-stamped video evidence. At one point, I was advised to drive the vehicle from Morgan Hill, CA to the dealership while making the loud noise for diagnostics — an unsafe recommendation. When the coolant warning light appeared, the service department planned only to top off coolant. I insisted on a diagnostic, which revealed a coolant hose leak. Driving with a leak could cause overheating and sudden engine failure, creating a serious safety hazard for myself, my child, and other motorists. Repair History: Multiple visits to Mercedes-Benz of San Jose (2024–2025) for the same defect. Each time, the defect was dismissed or not resolved. No meaningful repairs were performed. The issue persists today. Evidence: Time-stamped video proof of defect, full service records, and documentation of correspondence with the dealership are available. Safety Concern: This unresolved defect creates a risk of sudden engine failure or overheating while driving, potentially causing loss of control or stranding occupants in unsafe conditions.

My 2022 Mercedes-Benz GLC 300 has been diagnosed with a valve seat failure. This requires a full cylinder head replacement. I purchased this vehicle brand new and have driven it with care, putting approximately 60,000 mostly highway miles on it. Throughout my ownership, I have exclusively used the service at an authorized Mercedes-Benz dealership. Despite my efforts to maintain this vehicle properly, the vehicle began exhibiting misfire issues just outside of the warranty period. The check engine light would flash on and off during a misfire and it presented multiple codes. I returned to a Mercedes-Benz dealership, where I was told the issue is an internal mechanical failure, worn or leaking valve seats requiring full cylinder head replacement with an estimated repair cost of $7,800. Upon researching this issue, I've learned that Technical Service Bulletins exist for this exact failure, and other owners with M264-series engines have experienced identical symptoms and failures. This misfire could happen at anytime, requiring me to stop the vehicle almost immediately. It could cause a dangerous situation in heavy traffic areas with fast moving traffic.

The vehicle's steering wheel vibrates noticibly between speeds of 47 mph and 55 mph. This issue was once addressed with a "software update" by Mercedes Benz of Portsmouth, NH. Streering wheel vibration is a concern for any driver that rely on power steering to turn or hold the car steady. In addition it creates unnecessary panic for some drivers. This issue is brought to Mercedes Benz multiple times. I had replaced all the tires at 19,000 miles, balanced, got tires aligned by Mercedes Benz dealer and the issue persists.

While driving on the [XXX] at the speed of 10 to 15miles per hour, I noticed a smoke in the from hood on the passenger side. I felt a danger and stopped the car and got out of the car immediately along with my friend, leaving my belongings phone and other documents etc. Immediately it caught up the fire. I called 911 and reported the incident. Police and Fire engine arrived and tried to stop the fire. I have sent out an email to the dealership as the vehicle is under guaranty and i haven't got any courtesy call to know about the incident. When i tried to call them they didn't even respond to me and hung the phone. I received a call from their sales department and enquiring about if i'm looking for any other vehicle which disappointed me more. I'm in shock and would like this to be investigated as this major security concern. Here is the case# i have logged with manufacturer(Mercedes) Case#:[XXX] CASE#:[XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Safety was at risk when the gears switched to neutral while I was driving in car with my children. A recall was completed when bought car was not aware of fuel pumps recall issue. Says completed repair but the car is still having issues and was sold to me without telling me about the recall. First appeared about a week ago. Making a ticking noise, losing power when accelerating.

The contact owns a 2022 Mercedes-Benz GLC300. The contact stated while driving 76 MPH, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that the vehicle speed independently decelerated. The contact safely drove the vehicle to the shoulder of the road. The contact stated that a warning light illuminated indicating do not shift the gear, contact the dealer. In addition, the contact stated that the gear shifter seized, and the wheels locked up. The contact stated that the failure occurred while driving on a major highway. The vehicle was towed to the dealer. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The contact stated that the vehicle was serviced at the dealer in July 2024. The contact stated that several unknown repairs were completed. The manufacturer was not made aware of the failure. The failure mileage was approximately 20,370.

There is a significant steering vibration as the front wheel drops in a common pothole turning at speeds above 30 mph. There is a loss of control as if the wheel is skipping. It feels like the shock absorber continues to vibrate for a few seconds. I did mention this to Mercedes-Benz during the annual maintenance service but they did not do anything.