Mercedes-Benz C300 hesitation problems

Filed Dec 22, 2025 · Engine, Fuel system · FL

This vehicle was brought to an authorized Mercedes-Benz dealership for regularly scheduled maintenance. Shortly after this service, the vehicle began experiencing significant issues including difficulty accelerating, engine hesitation while driving, and noticeable shaking at idle. This car has never overheated. The vehicle was returned to the dealership for inspection. The dealership diagnosed a cracked cylinder head and advised that the repair requires replacement of the cylinder head at an estimated cost of approximately $11,000. The failed component is available for inspection and the vehicle is currently at the dealership. The vehicle has approximately 46,000 miles, has been regularly maintained, garaged, and driven under normal conditions. These symptoms created engine performance issues that could result in loss of power or inability to accelerate while driving, creating a potential safety risk, especially in traffic or at highway speeds. I regularly transport my young grandchild in this vehicle. The possibility of sudden engine failure, loss of power, or breakdown while driving raises significant safety concerns for myself and any passengers, particularly a young child. The failure has been confirmed by an authorized Mercedes-Benz service center. During my own research, I discovered there have been recalls involving similar engines for the same model year, as well as multiple owner complaints reporting similar engine or cylinder head failures on this vehicle. I contacted Mercedes-Benz customer care on December 17, 2025, after receiving the dealership diagnosis, and was advised that I would receive a response within 72 hours. As of today, I have not received any response. I attempted to call customer care again, but the phone system would not accept a voicemail and no representative answered. My case number with Mercedes-Benz is 19653254. No prior abuse, misuse, or abnormal driving conditions occurred. The vehicle was properly maintained.

Filed Nov 19, 2025 · Acceleration, Fuel system · GA

1. The vehicle experienced a fuel injector failure, which is part of the engine fuel delivery system. This failure appears connected to an open Fuel System Control Unit Software Update Recall (Campaign 2024080006) that has been open since May 2024 but was not performed on my vehicle, despite the vehicle being serviced at the dealership in January 2025 for other recall-related updates. The failed injector is still available for inspection upon request. 2. The vehicle began exhibiting symptoms of fuel system malfunction while driving, including rough idling, hesitation, and loss of power. A malfunctioning injector can cause the engine to misfire, stall unexpectedly, or run unpredictably, which creates a high-risk situation in traffic. This placed me, my passengers, and other drivers at risk, especially during acceleration or when merging into traffic. 3. Yes. The issue was diagnosed and confirmed by the Mercedes-Benz dealership, which stated that the injector had mechanically failed. The dealership also noted the open recall for the fuel system software update but claimed it was unrelated. I am seeking clarification because the timing and symptoms suggest there may be a connection. 4. The vehicle has been inspected only by the Mercedes-Benz dealership. Mercedes-Benz USA (MBUSA) has been contacted regarding the issue, but my case was closed without resolution and is currently awaiting review for reopening. MBUSA has not yet inspected the vehicle or the failed component directly. 5.Prior to the injector failure, the vehicle displayed engine hesitation, rough idling, and intermittent performance issues. Eventually, a check engine light illuminated. These symptoms began before the manufacturer-installed software update, and the issue appears to have worsened afterward.

Filed Oct 4, 2025 · Electrical, Engine · CA

I am writing to formally report an ongoing issue and safety concern with my vehicle. Since the day I purchased the car, I have experienced numerous mechanical problems and have spent a significant amount of money on repairs. In August, I had to take my vehicle to a local repair shop three times due to persistent issues. The car was also towed by AAA three separate times for safety reasons. My main concern is that the vehicle hesitates during acceleration and feels sluggish while driving, which creates a serious safety risk on the road. I contacted Mercedes-Benz and filed a claim regarding this issue; however, I have not received any meaningful assistance or resolution. I am requesting that this matter be re-evaluated and properly addressed as soon as possible, as my safety and the reliability of the vehicle are at risk. Please confirm receipt of this message and advise me on the next steps or any documentation needed to proceed with my claim. Thank you for your prompt attention to this matter. [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 16, 2023 · Electrical, Fuel system · 5,000 miles · IL

The contact owns a 2022 Mercedes-Benz C300. The contact received notification of the federal safety agency Campaign Numbers: 23V445000 (Fuel System, Gasoline) and 23V462000 (Electrical System) however, the part to do the recall repairs were not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. Additionally, the contact stated that on several occasions, the vehicle failed to start. The contact stated that she had to wait for an undisclosed amount of time to restart the vehicle. An unknown warning light was illuminated. The contact then stated that while driving at an undisclosed speed, the vehicle hesitated and stalled. The contact was unable to restart the vehicle. The contact stated that she felt unsafe driving the vehicle and was concerned for her safety. The dealer was not notified of the failure. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and the contact was advised to contact the federal safety agency Hotline. The failure mileage was approximately 5,000. VIN tool confirms parts not available.

Filed Oct 9, 2023 · VA

In the past few months while driving this car in the Washington DC metro area at normal road speed, the car has suddenly and unexpectedly lost driver power. Each time, I have pushed down on the gas pedal, and after some hesitation the car has moved forward, and then continued to operate normally. This has happened three times in the past 3-4 months.

Filed Mar 2, 2023 · Engine · 90,449 miles · CA

The contact owns a 2015 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the vehicle hesitated and stalled. The check engine warning light was illuminated. The vehicle was towed to Safety Auto Repair where it was diagnosed that the engine failed and needed to be replaced. The vehicle was not repaired. Neither the dealer nor the manufacturer was notified of the failure. The failure mileage was approximately 90,449.

Filed Feb 3, 2023 · Engine · PA

My check engine light came on at about 68,800 miles. The OBD code shows that I need the Positive Crankcase Ventilation valve replaced. The repair for this is approximately $2,300 and requires about six hours of shop labor, and the part costing over $425. I’ve never known a PCV replacement on any vehicle to be more than $60, with the part itself being about $10-$20. Most times, the part can be simply cleaned and replaced. This is very disappointing. Especially given that the engine design, just two years prior, would have been less than $200 for the same repair, with part costing about $60. The vehicle does not show any symptoms of the part being blocked, as indicated in the code. There is no hesitation, loss a power or decline in fuel efficiency. However, the engine light cannot be turned off until the part is replaced. I think that $2300 to replace a part on seven year old car, well under 100,000 miles is indicative of either poor design or predatory. Hopefully, something can been done to address this. Thank you!

Filed Jun 10, 2021 · CA

My daughter was driving at freeway speeds, when she heard, what we now know, is a portion of the sunroof panel flapping and break off. There was no warning, no instrument indication, and assume the broken part was a safety hazard to vehicles following. We took her vehicle to Fletcher Jones Mercedes in Newport Beach, but they're hesitating about repairing or reimbursing costs, due to the pending nature of the federal safety agency Recall #21V197.

Filed Nov 4, 2019 · Engine · 58,000 miles · CA

Tl* the contact owns a 2015 mercedes-benz c300. While the contact's daughter was driving at an unknown speed, the vehicle failed to accelerate and began to hesitate. In addition, the check engine warning indicator illuminated. The driver was able to park on the side of the road. The vehicle was towed to mercedes-benz of stevens creek (located at 4500 stevens creek blvd, san jose, ca 95129, (408) 641-4610) where it was diagnosed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not notified. The failure mileage was 58,000.

Filed Sep 27, 2018 · Airbags, Transmission · 100,000 miles · TX

My car has two recalls for the airbags which means my car can not be traded in because it's not resaleable. These recalls are not minority's and we risk serious injury or possible death because mercedes can fix the problem. Reassuraning knowing if you're ever in an accident your airbags may distinction during impact or be the reason you die. I'm stuck with this car until the remedies are available, but I'm also stuck with risking my life. I started having transmission problems with hesitating to speed up from a stop or slower speed. The dealership said it was my intake manifold flap that needed to be replaced. Of course that wasn't the problem and it's getting worse. I had it looked at again to be told nothing was wrong and no codes were displayed during the diagnostic check. Meanwhile my car gets worse by the week and my transmission feels like something is clearly wrong. For the third time I had it checked and this time had a technician ride with me. He noted the hesitating feeling while driving and validated my concerns. He said he personally believes my transmission is malfunctioning but mercedes is covering their tails. He suggested I take it to a private mechanic who specializes in mercedes unless I want to pay $9,000 to mercedes to be told a range of things need to be fixed and the problem never be solved. Absolute rip off and I'll never buy mercedes again.