⚠️ Mercedes-Benz manufacturer position
XENTRY documents fuel pump access via rear seat service opening on W177 sedan. Contaminated fuel is not covered by warranty.
Vehicle information
| Make | Mercedes-Benz |
|---|---|
| Model | A-Class |
| Market status | A-Class sedan sold new in the US 2019–2022 (gasoline; hatch not sold US) |
| Body styles | Sedan (US) |
| Generations | W177 sedan (US 2019–2022) |
| Engine options | Gasoline: 2.0L turbo I4 (A 220, A 35 AMG) |
| Fuel tank capacity | 11.4 gal (43 L) — varies; consult OEM for model year |
| Fuel system | Gasoline direct injection |
| Access method | Fuel pump access under rear seat (typical W177 sedan) |
| Anti-siphon | Yes |
| Service portal | Mercedes-Benz XENTRY / Star TekInfo |
Misfuel risk Moderate
Compact Mercedes sedans are gasoline-only in the US—diesel nozzle errors are the main risk.
If the engine was not started
Do not start. Drain via pump module access; refill with required gasoline grade.
If the engine was started
Inspect HPFP and injectors; replace fuel filter; clear adaptations per XENTRY.
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
- US did not receive A-Class hatchback—imported hatches are rare private imports.
Frequently asked questions
Is the US A-Class diesel?
No. US-market A-Class sedans were gasoline turbo models only.
Where is the fuel pump on an A-Class sedan?
XENTRY typically specifies rear seat cushion removal and service cover for the pump module.
What octane after a drain?
Use the grade on the fuel door—often premium for AMG Line trims.
Need professional misfuel recovery?
Find a certified operator or read consumer guidance for your next steps.
Find an operator Consumer guidance