Mercedes-Benz GLE 350 loss of power problems

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 May 28, 2026 · Engine · CA

The engine in my 2020 Mercedes-Benz GLE 350 experienced catastrophic internal failure while driving. No warning lights or check engine indicators came on. Prior to failure, the vehicle began making a loud metallic knocking/rattling sound during acceleration, similar to “rocks shaking in a box.” Shortly afterward, the engine suddenly stalled while driving and would no longer run. The vehicle still had electrical power but the engine would not restart. The vehicle was towed to Mercedes-Benz of Las Vegas for inspection. The dealer diagnosed the engine as seized and documented metal debris in the oil filter and oil/metal debris underneath the vehicle, indicating catastrophic internal engine damage. The dealer stated that the engine replacement was required.The failed engine and vehicle are currently located at Mercedes-Benz of Las Vegas and are available for inspection upon request.The vehicle stalled unexpectedly while being driven on a public roadway, causing sudden loss of engine power and creating a potentially dangerous traffic situation. The violent shaking and knocking before failure also caused concern that the vehicle could lose control or stop operating completely in traffic, which it ultimately did. A sudden engine seizure and stall while driving creates a significant safety hazard because the driver may lose the ability to accelerate, maneuver safely, or clear traffic. This could increase the risk of collision, especially at highway speeds or in heavy traffic conditions. Mercedes-Benz of Las Vegas inspected the vehicle and confirmed catastrophic engine failure. The dealer documented that the engine was seized and that metal debris was found in the oil filter and underneath the vehicle. The dealer advised that the engine required replacement and provided an estimated repair cost exceeding $27,000. The dealer has not yet identified the root cause of the failure. No dashboard warning lights, oil pressure warnings, or check engine lights illuminated.

Filed May 23, 2026 · Electrical, Engine · VA

We were traveling to our son’s college graduation, driving on a rural interstate and suddenly all of the vehicle’s warning lights lit on the dash and the car started losing, and then completely lost power. The car was no longer operational. We were stranded on the roadside of a remote but busy 2-lane interstate for 2 hours until a tow truck could arrive and take the car to the closest car repair shop which was 45 minutes away. This was an incredibly dangerous situation and we were fortunate to be alongside the shoulder, although we were still close to the tractor trailers and cars on the interstate. (Because we were stranded in such a remote place, we had no other options to get to our son’s graduation. We were unable to attend because of this.) The rural repair shop the car was initially towed to could not determine the problem. A few days later we found a 2nd tow truck that agreed to bring the vehicle several hundreds of miles back to our home city. This car is a 2020 model, and has around 55,000 miles. It has been meticulously maintained by a certified Mercedes mechanic. There were no issues with the car and no indication that there might be a problem. Our mechanic has thoroughly inspected the vehicle and said that the engine has completely seized and the only option is to replace it. We have no idea why this happened. If requested, the vehicle is available for inspection.

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 31, 2025 · Engine · GA

Engine Cylinder Head Failure on CPO Mercedes-Benz GLE 350 Vehicle Information: •Make: Mercedes-Benz •Model: GLE 350 •Year: 2020 •Mileage at time of issue: 90,000 Summary of Complaint: The vehicle experienced a premature cylinder head failure, resulting in significant engine damage and repair costs. There were no prior warning lights or diagnostic codes indicating a problem before the failure occurred. The malfunction caused sudden performance issues, including rough idling, misfiring, and loss of power. Details of the Incident: While operating the vehicle under normal driving conditions, the engine began to run roughly and lost power unexpectedly. Diagnostic testing revealed that the cylinder head had failed, which appears to be a mechanical or manufacturing defect rather than wear and tear. The repair estimate from the dealership was approximately $8,900, which is disproportionately high for a vehicle of this age and mileage. Safety Concerns: This type of failure could lead to sudden engine shutdown or loss of power while driving, posing a safety risk to occupants and other drivers on the road. Manufacturer Case Reference: This issue has also been reported to Mercedes-Benz under case number 18281587. Additional Information: After research, it appears that other Mercedes-Benz GLE owners have reported similar issues related to engine component failures, suggesting this may be a broader quality or manufacturing issue that warrants investigation. Requested Action: Requesting that the federal safety agency investigate potential defects in the engine or cylinder head assembly for the 2020 Mercedes-Benz GLE 350 and determine whether a recall or service bulletin is appropriate.

Filed Oct 20, 2025 · Engine · NY

I am writing to express serious concern regarding a potentially dangerous mechanical issue with my Mercedes GLE 350. The vehicle has experienced a complete cylinder head failure, requiring an estimated $7,000 repair. Both an independent service center and an authorized Mercedes service center have confirmed this diagnosis. During the inspection process, Mercedes conducted two diagnostic tests—one costing $250 and a second costing $700—before determining that the cylinder head must be replaced. I was informed by the Mercedes service advisor that the company is aware this issue has affected other GLE 350 vehicles; however, no recall has been issued to date. This failure presents a significant safety risk. The vehicle suddenly loses power without warning, and acceleration becomes severely limited, often not exceeding 20–40 mph even when pressing the accelerator fully. The check engine light illuminates at the time of power loss, leaving the driver unable to maintain safe highway speeds or merge with traffic—posing a serious hazard to both the driver and others on the road. Given that this appears to be a known issue, I am requesting immediate review and investigation by Mercedes-Benz. A recall or formal service campaign should be considered to address this potentially dangerous defect and to ensure the safety of all affected drivers. Thank you for your prompt attention to this matter.

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 Aug 11, 2025 · Engine · OR

The vehicle recently experienced a cylinder head failure, confirmed by a diagnotic code P0302 (Misfire in cylinder 2), resulting in rough idling, reduced power, and potential safety risks during opreration. This issue appears to be a known defect in the M264 engine, as evidenced by similar complains from owners of GLE 350, GLC 300, and other models on forums like [XXX] and [XXX] . The failure occurred just beyond the standard 4-year/50,000-mile warranty, and Mercedes-Benz USA denied my request for a goodwill repair despite acknowledging similar issues in related models under extended warranties. Repair costs are estimated $8,000 to $13,500. I believe this defect warrants investigation due to its prevalence and potential to cause sudden power loss, which could lead to hazardous driving conditions. I urge the federal safety agency to investigate the M264 engine in the 2020 GLE 350 for a possible recall to protect owners and ensure safety. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)