2021 Mercedes-Benz GLE 350: sudden loss of power

Filed Jun 3, 2026 · Engine · CA

At approximately 87,000 miles, my 2021 GLE350 (M264 2.0T engine) experienced a severe engine misfire resulting in a flashing check engine light, rough idle, engine shaking, significant loss of power, and near-stall condition. The vehicle was taken to Speedhaus Automotive (Newbury Park, CA) where all four ignition coils and spark plugs were replaced. Total repair cost was approximately $635. This failure pattern is consistent with the documented M264 exhaust valve seat wear issue acknowledged by Mercedes-Benz technicians. A Mercedes dealer service report on an identical 2021 GLE350 explicitly states: "COMMON ISSUE FOR EXHAUST VALVE SEATS TO WEAR — KNOWN ISSUE WITH 260 AND 264 MOTORS." Mercedes-Benz has extended the warranty on the M260 engine (transverse variant) for this identical failure mode but has not extended it for the longitudinally-mounted M264 despite the same defect being present. Repair costs for full cylinder head failure on the M264 are being quoted at $6,000–$13,000. I am requesting the federal safety agency investigate whether a safety recall is warranted for the M264 engine across all affected GLE350, GLC300, C300, and E350 vehicles.

Filed Jan 8, 2026 · Engine · FL

There is a known issue with the Cylinder Heads on specific models of Mercedes vehicles. Symptoms of M264 Cylinder Head Failure If your GLE 350 is experiencing these symptoms, it may be covered under the extension: Check Engine Light (MIL): Often triggered by misfire codes. Rough Idle: Noticeable shaking or uneven idling when stopped. Loss of Power: Potential stalling or significant power reduction during acceleration. Low Compression: Diagnostic tests often reveal low pressure in one or more cylinders. This is not being addressed my Mercedes USA where Mercedes Canada has offered an extended warranty. Using social media I have comprised a list of over a hundred impacted owners. Many more exist. What this does is cost catastrophic failure of the engine leaving the driver stranded in whatever lanes they were traveling in. I am disabled and for me this created a life threatening situation. When reaching out to MBUSA the answer is simply "not warranty exists" where MB Canada has extended the warranty to an additional 15k miles from notice. My engine blew. The replacement cost is near $20,000 dollars. The mileage on my engine was 65k. Many others are impacted and a class action lawsuit is the only other course of action it seems. Regards, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Dec 18, 2025 · LA

My vehicle suddenly started shaking and losing power, the check engine light came on and the problem continues to vibrate when idling, it will not shift into gear to go. Very unnerving and unsafe as it happened in a intersection. Sometimes it drives fine and then vibrates and goes into low gear and loses power. I took to a certified Mercedes dealer and they changed the spark plugs and 4 coils as well - After 4 weeks, I am told the CYLINDER HEAD needs to be replaced. It has 68k miles. The mechanic has already had 2 other 2021 GLE 350 with exactly the same issue. There are several similar cases discussed online as well.

Filed Oct 14, 2025 · Transmission · TX

Location: Dallas, TX – Woodall Rodgers Freeway near North Hall Street exit Mercedes-Benz USA Case #: 18469650 What component or system failed or malfunctioned, and is it available for inspection upon request? The vehicle’s 48-volt electrical architecture appears to have failed, specifically the DC/DC converter or Integrated Starter-Generator (ISG) that provides 12-volt power to all control modules. When this component failed, it caused a total loss of propulsion and electrical power. The vehicle is currently at a Mercedes-Benz dealership in Dallas and available for inspection upon request by the federal safety agency or Mercedes-Benz USA (case #18469650). How was your safety or the safety of others put at risk? While driving approximately 50 mph on the Woodall Rodgers Freeway with my family in the car, the vehicle suddenly lost all engine power and throttle response without warning. The accelerator stopped responding, and the engine stalled completely within seconds. I was able to coast partially onto an exit ramp, but once stopped, the car would not restart and could not be shifted into Neutral. We were stranded in live traffic with limited steering assist and no way to move the vehicle, placing my family and other motorists at serious risk of collision. Has the problem been reproduced or confirmed by a dealer or independent service center? The vehicle is currently at a Mercedes-Benz authorized dealer, and the failure has been logged with Mercedes-Benz USA under case #18469650. Initial findings point to a malfunction of the DC/DC converter or 48-volt system. Full STAR diagnostic data and fault codes are pending. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? Mercedes-Benz USA has been notified and opened case #18469650. The vehicle has been inspected by the dealership’s certified technicians and is awaiting official diagnostic reporting and possible engineering review through Mercedes’ Technical Assistance

Filed Sep 19, 2025 · Engine · IN

I am writing to document a recurring and serious issue with the Mercedes-Benz GLE equipped with the M264 engine, specifically relating to premature cylinder head failure. In my case, the vehicle began showing the following symptoms: Rough engine idle and noticeable vibration during startup Loss of power, especially when accelerating Check engine light with fault codes related to misfire or combustion issues Oil and/or coolant loss, with no external leaks Engine knocking or ticking noises near the top end of the engine After a professional inspection and diagnostic testing, I was informed that the issue is likely due to a defect or failure in the cylinder head, possibly involving warping, cracking, or failure of the valve seats or head gasket area. Upon further research, I discovered that this issue is not isolated. Multiple owners of vehicles with the M264 engine—including various GLE, C-Class, and E-Class models—have reported similar problems, often occurring well before 70,000 miles and despite regular maintenance. The pattern suggests a possible design flaw or quality issue with the engine’s cylinder head. As of now, it appears no formal recall or technical bulletin has been issued by Mercedes-Benz regarding this specific problem. However, the number of similar reports suggests the issue is widespread enough to merit formal investigation or at least acknowledgment by the manufacturer.

Filed Dec 6, 2024 · Engine · TX

On August 6, 2024 my vehicle reported " The state of charge of the starter battery in the vehicle Mercedes-Benz GLE 350 SUV is very low". We took it to our local dealership to have the battery replaced but upon receiving the vehicle we started having issues. The vehicle would shake and loose power. Upon turning off and turning back on the vehicle would continue working properly. We proceeded to have a local shop diagnose it since our 2021 vehicle was about 10k over the covered warranty and our local MB dealership is not very efficient. They recommended remove and replace engine cylinder head assembly. The warning lamp was for the battery and what followed after the starter battery getting replaced was the engine light. The problem that was concerning was the loss of power driving on the expressway. The vehicle is available for inspection upon request. Vehicle diagnosis from shop available upon request.