2017 Mercedes-Benz C300: fuel pump failure

Filed May 15, 2026 · Electrical, Engine · 65,422 miles · CA · fire

The contact owns a 2017 Mercedes-Benz C300. While driving at approximately 15 mph, the contact observed smoke emanating from under the hood. The vehicle was driven to her work location and parked. Upon exiting the vehicle and opening the hood, she observed orange flames coming from the engine compartment. A parking attendant extinguished the fire, and a police and/or fire report was filed. The vehicle was towed to a dealer and diagnosed with a fuel line leak that caused the engine harness to come apart. The leaking fuel hose from the high-pressure fuel pump caused damage to the high-pressure pump, engine harness, vacuum transducer, and coolant feed line from the thermostat to the firewall. The following components needed replacement: high-pressure fuel pump, rubber fuel hose, engine harness, pressure transducer, and intake manifold. The vehicle was repaired. Five months later, the contact experienced another failure she believes was associated with the engine fire. While parked and attempting to start the vehicle, it did not start. The vehicle was towed to a dealer and diagnosed with a faulty starter that needed replacement. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 65,422.

Filed Oct 30, 2025 · Body, Electrical · TX

I am reporting a serious vehicle safety hazard caused by improper and unsafe repair work performed by USA Platinum Motor, located at 1221 California Lane #126B, Arlington, TX. I brought my 2017 Mercedes-Benz C300 in for a cold start rattle with no warning lights or prior issues. The shop diagnosed a loose timing chain and I authorized the repair. After the repairs, the vehicle was returned with critical safety defects, including a loose fuel pump, unsecured fuel line, missing bolts, and improperly reassembled engine components. Shortly after pickup, the car experienced loss of acceleration on the interstate, a strong odor of fuel, and a sudden loss of power, creating a dangerous and life-threatening situation. The vehicle had to be towed back to the shop. The manager, who is not a certified mechanic, admitted he personally “fixed” the issue by tightening the fuel pump himself. A Mercedes-Benz diagnostic inspection later confirmed multiple severe assembly errors, including missing fasteners, unsecured oil cooler, disconnected vent lines, and other safety-related defects in the fuel and cooling systems. These unsafe and negligent repairs created an extreme fire hazard, engine instability, and risk of sudden failure while driving. I am requesting a formal the federal safety agency investigation into this matter to ensure vehicle safety compliance and to prevent similar incidents affecting other consumers.

Filed Dec 19, 2023 · Fuel system · NY

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 The entire interior smells like gasoline, really bad.

Filed Aug 22, 2021 · Fuel system · GA

MB USA extended the warranty coverage on the low pressure fuel hoses that connects to the high pressure fuel pump. The reason is "under certain cold ambient conditions during a cold start of the engine, the low pressure fuel hose at that connection may experience slight fuel weeping". MB USA, however, ruled out a safety risk. the federal safety agency needs to investigate it. If MB USA found the fuel pressure line is defective, they needed to do a recall. I believe it must be a recall as fuel leaks is not only a safety risk but also a serious health hazard to the occupants. What if the occupants have sinusitis and don't smell well. What if the leaks is too small to smell enough but can still be a health issue.

Filed Feb 13, 2021 · Fuel system · 47,000 miles · TN

A fuel line in the engine compartment just above the skid plate on the drives side just right of the front wheel well leaks fuel where the line is crimped coming from the high pressure fuel pump. Fuel collects on the skid plate and when a stop at idea produces a strong fuel smell in the cabin of the car