2012 Mercedes-Benz C300 fuel system problems

Filed Sep 12, 2026 · Fuel system · WI

Fuel tank is rusting. Leaking fuel, heavy fuel smell inside cabin. My saftey and anyone around the vehicle would be at risk due to fire chance. Confirmed by independent service center Vehcile has only been inspected by me and the shop Only symptom that appeared was fuel smell in my garage and a puddle of gasoline underneath the vehicle.

Filed May 19, 2026 · Fuel system · MA

Vehicle: 2012 Mercedes-Benz C300 4Matic Sport Problem Component: Fuel / Propulsion System Safety Issue Description: My 2012 Mercedes-Benz C300 developed a serious fuel tank leak at approximately 106,460 miles which created overwhelming gasoline fumes and rendered the vehicle unsafe to operate. The gasoline fumes were extremely strong and entered the passenger area. The fumes were severe enough that I became physically overwhelmed from the gasoline exposure and discarded clothing due to gasoline contamination and odor. A local repair facility identified the leaking fuel tank. I was informed the replacement fuel tank was allegedly on extended backorder through Mercedes-Benz channels. Because the vehicle was unsafe to drive and replacement parts were allegedly unavailable for several months, I was forced to tow the vehicle from [XXX] to [XXX] at my own expense in order to locate a repair facility that could obtain a replacement fuel tank and safely repair the vehicle. The repair invoice states: “Installed used lt fuel tank incl switchover fuel pumps replace section of steel fuel line front of tank from lower braided line.” I am submitting this complaint due to: serious gasoline leak safety concerns, severe gasoline fume exposure, potential fire hazard, and the alleged extended unavailability of replacement fuel tanks. Mercedes-Benz USA Case Number: 22302114 INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 28, 2025 · Fuel system · 98,000 miles · SC

The contact owns a 2012 Mercedes-Benz C300. The contact stated the fuel tank was emitting a fuel odor. The contact stated that the fuel odor was extremely strong and could be smelled inside the residence while the vehicle was parked in the garage. There were no warning lights illuminated. The vehicle was taken to a Certified Mechanic, who diagnosed that the leak was coming from the top of the fuel tank; however, the mechanic was unable to specify the cause. The vehicle was towed to the dealer, but the vehicle was not diagnosed. The vehicle was not repaired. The contact became aware of the federal safety agency Campaign Number: 12V557000 ( Fuel System, Gasoline) online; however, the VIN was not included. The manufacturer was informed of the failure and informed the contact that the VIN was not under recall. The failure mileage was approximately 98,000.

Filed Apr 20, 2023 · Brakes, Fuel system · 96,000 miles · CT

The contact owns a 2012 Mercedes-Benz C300. The contact stated while driving at various speeds, extra brake travel time was needed to stop the vehicle. There was no warning light illuminated. The contact had taken the vehicle to an independent mechanic where the vehicle was purchased, and he was informed that the failure was caused by the new brake pads placed on the vehicle. The contact eventually took the vehicle to a dealer and was informed that the fuel tank and brake lines were corroded; and the contact was provided an estimate for the repair. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 96,000.

Filed Jan 20, 2023 · Fuel system · 109,000 miles · MD

The contact owns a 2012 Mercedes-Benz C300. The contact stated that while parked, the vehicle failed to start. The vehicle was towed to the dealer where it was diagnosed as having water intrusion. The vehicle was not repaired. The contact referenced the failure to the federal safety agency Campaign Number: 22V955000 (Fuel System, Gasoline, Fuel System, Diesel). The manufacturer was made aware of the failure. The failure mileage was approximately 109,000.

Filed Oct 23, 2022 · Fuel system · IL

Car is leaking gas very dangers . I contact Mercedes dealer regarding the recall on this type of Mercedes i have and they said only vehicles manufactured from April 18, 2011, through July 12, 2011. Mine was before or after , and they refuse to give me the exactly date for my car manufacturer. Car I use for Uber , and i don’t have any other income . If someone just through away a cigarette in parking lot might cause a big problem in the building and others cars in parking

Filed Oct 11, 2022 · Fuel system · IL

My Mercedes 2012 C 300 is leaking gas which may lead to fire ( the fuel filter flange when operated in high temperatures

Filed Jul 15, 2022 · Fuel system · AZ

My car smell like a gas leak. I had went to a car shop to have the car to looked at. The mechanic had told me that the fuel filter flange is leaking gas.

Filed Oct 6, 2021 · Brakes, Fuel system · NJ

The rear drivers side had a loud chunking/clanking noise while driving and the vehicle was unable to control and break when in motion. Driving was impossible as the breaking component was a total failure and car could not be controlled while traveling down 45-50mph zone. I reduced my speed to 20-25 mph by letting off on the gas to get better control of the car if breaking would need to be suddenly made. I relied on the shoulder to pull off if any sudden breaking was needed. The car was immediately take to be reviewed by a specialized Mercedes benz mechanic and further inspection proved that the rear subframe on the driver’s (left) side was corroded and broken. The connecting arms are rusted, corroded and rendered the car inoperative. I notified my insurance company as well as car manufacturers corporate office. I researched this issue further and discovered that this reoccurring issue with this make and model. There are a pheletera of recounting of this same issue on various message boards to validate the same issues and callouts I found. The car was taken to the dealership that it was purchased and further inspection showed that the left side subframe/ subframe arms were corroded with rust and broken. The brake lines and fuel tank were equally rusted and corroded. The service manager confirmed that this is defect of the car but it had been part of a recall. I had the car towed for 2nd opinion to another dealership service department to access the car and this callout further validated the corrosion and rust was wide spread and has rendered the car inoperable unless these damages were fixed.

Filed Sep 2, 2020 · Fuel system, Steering · 92,000 miles · WV

The rear subframe has corroded around the areas where the trailing arm and control arm meet the subframe on both sides of the vehicle, and has disintegrated around the drivers side rear trailing arm causing it to have detached, along with a piece of the subframe. The metal of the subframe is distorted around the area of the break. The detached trailing arm and piece of subframe are now making contact with the fuel tank as well. The fuel tank could have easily ruptured and ignited when this car was still in operation, as this car was driven for several days before the manufacturing defect was discovered. The failure happened when coming to a gentle stop from 20-30 miles per hour on a straight road. There was a loud snapping noise from the drivers side rear. This car had 92,000 miles at time of the structural failure and has been regularly serviced, exclusively at mercedes-benz. Mercedes-benz USA customer service is unable to offer any assistance. This exact issue has LED to a recall of the same model in canada, and there are countless the federal safety agency reports describing similar structural failures. Mercedes-benz USA is aware of this issue and is also aware that there is a recall in canada, but has made it clear that goodwill will not be extended.