⚠️ Mercedes-Benz manufacturer position
XENTRY covers pump access through trunk floor on sedans and tank removal when required. PHEV requires HV disable before fuel work.
Vehicle information
| Make | Mercedes-Benz |
|---|---|
| Model | C-Class |
| Market status | Sold new in the US 1994–present; US diesel offerings largely withdrawn after ~2018 |
| Body styles | Sedan, Coupe, Cabriolet (availability varies by year) |
| Generations | W206 (2022+); W205 (2015–2021); earlier W204/W203 |
| Engine options | Gasoline: 2.0L turbo I4; 3.0L turbo I6 (AMG); varies by year Diesel: BlueTEC diesel on select older US model years—verify VIN Hybrid: C 350e PHEV (select years) |
| Fuel tank capacity | 17.4 gal (66 L) typical W205/W206 |
| Fuel system | Gasoline direct injection; diesel models use common-rail BlueTEC |
| Access method | Trunk floor pump access (sedan) | Tank drop when documented |
| Anti-siphon | Yes |
| Service portal | Mercedes-Benz XENTRY / Star TekInfo |
Misfuel risk Moderate
Most new US C-Class sales are gasoline. Remaining US diesel C-Class in service still face gasoline-in-diesel risk.
If the engine was not started
Identify diesel vs gasoline from fuel door. Do not start. Drain per XENTRY.
If the engine was started
Diesel with gasoline run: common-rail components; gasoline with diesel: injectors and catalyst checks.
Access procedure
- Relieve fuel system pressure per OEM service information (disconnect pump fuse/relay or use scan tool as specified).
- Disconnect the negative battery cable.
- Access the fuel pump module per OEM (rear seat service hole, trunk floor, or cargo area—varies by model).
- Disconnect fuel lines and electrical connectors at the pump module using line-specific tools.
- Drain the tank into approved Class 3 containers; bond/ground per OSHA 29 CFR 1910.106.
- Inspect the tank interior; replace in-tank filter if contaminated or per OEM.
- Reinstall the pump module with a new seal; reconnect lines and wiring.
- Refill with the correct fuel grade; prime the system and check for leaks before road test (Mercedes-Benz procedure).
Notes
- 48V mild hybrid on some W206—follow battery disconnect steps in XENTRY before fuel service.
Frequently asked questions
Does Mercedes still sell C-Class diesel in the US?
Mercedes largely exited US passenger diesel around 2018. Confirm your model year—many US C-Class are gasoline.
I put diesel in my C300—what now?
Do not start the gasoline engine. Drain the tank via OEM access before the fuel pump primes.
C-Class coupe same tank access as sedan?
Procedures differ by body style in XENTRY—use the correct body variant for your VIN.
Need professional misfuel recovery?
Find a certified operator or read consumer guidance for your next steps.
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