2016 Mercedes-Benz C300: fuel pump failure

Filed Oct 22, 2025 · Fuel system · MA

The contact owns a 2016 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the contact smelled a gasoline odor in the interior of the vehicle. No warning lights were illuminated. The vehicle was taken to the dealer, who determined that the fuel hose downstream of the fuel pump was leaking. The vehicle was not repaired. After investigating the failure, the contact related the failure to the federal safety agency Campaign Number: 18V837000 (Fuel System, Gasoline); but the VIN was not included. The manufacturer was notified of the failure but provided no assistance. The failure mileage was unknown.

Filed Dec 8, 2023 · Fuel system · TX

Mercedes Benz Selma, Texas Dearlership refuses to service known issue with fuel system leaks on C300 because they cannot reproduce problem. Problem is that don't have the correct environment to test for this know problem. “There is a short rubber fuel line/hose in the engine compartment that is attached with compression clamps; the hose connects the fuel line from the gas tank to the high pressure fuel pump. When it gets cold outside (below ~40 degrees Fahrenheit) the clamps loosen a bit and the hose will leak gas. This is what you will smell in the cabin. Once it gets warmer outside or the engine bay warms up, the smell will tend to go away. No clue how they've gone all this time without a safety recall, but I did make a report to the NHTSB last month when it started happening to me.” The fix is to have the rubber line w/clamps replaced. If you still have warranty the dealer can take care of it. (Provided they are configured to test for this defect properly which they are not. Bottom line, fuel leaks in garages like mine with a gas water heater are a BIG issue. I alerted the dealership that they and MB would be liable if something were to happen since they refused to repair vehicle.

Filed Jan 5, 2023 · Engine, Fuel system · 83,000 miles · DC

The contact owns a 2016 Mercedes-Benz C300. The contact stated he noticed an abnormal fume odor entering through the air vents of the vehicle. The contact self-diagnosed the vehicle as having a fuel leak from the fuel pump. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 83,000.

Filed Aug 8, 2022 · Fuel system · 61,000 miles · SC

The contact owns a 2016 Mercedes-Benz C300. The contact stated while driving 45-60 MPH, the vehicle began to stall. The contact depressed the accelerator pedal several times but the vehicle failed to respond. The vehicle stalled. The contact was able to veer to the side of the road. The contact was able to restart the vehicle. The check engine warning light and several unknown warning lights were illuminated. The vehicle was towed to the contact’s residence. The vehicle was then towed to the local dealer where it was diagnosed that the fuel pump and fuel tank needed to be replaced. The vehicle was being repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 61,000.

Filed Feb 7, 2022 · Fuel system · MA

Fuel leak from fuel lines from high pressure fuel pump. This is a common problem for C300s from 2015 to 2019, especially in cold weather. Fumes in cabin and fire risk in engine compartment.

Filed Jan 25, 2020 · Engine · GA

Fuel smell in cabin - fuel leak in engine compartment. From dealer invoice: found fuel line leaking from rubber line that comes from bell housing fuel line connector to high pressure fuel pump on engine head.. R and r battery ground.. R and r belly panels.. Depressurize fuel system.. Replaced rubber fuel line that comes from bell housing fuel line connector to high pressure fuel pump on engine head.. Cleaned away contrast spray and test drove again,, problem is resolved.

Filed Dec 18, 2019 · Fuel system · 33,100 miles · CA

Hose clamps attaching the high pressure fuel line leading from the firewall-mounted fuel pump to the central fuel rail failed to maintain a tight connection. This leads to fuel leaking past the hose clamp connection into the open engine compartment during cold weather (sub-40 degrees fahrenheit) while the engine is running. When the ambient temperature in the engine compartment rises, either by environment or by heat generated from the engine, the fuel leak subsides. Symptoms when this occurs are a very strong fuel smell in the passenger compartment and also, upon further inspection, observation of liquid fuel pooling on the top side of the engine compartment under tray. Internet research also indicate that this is a fairly widespread problem affecting at least 2015-16 w205 model vehicles, and that multiple mercedes-benz dealerships in the united states have communicated verbally to other customers that this is a "known issue".