Engine and gearbox (P)
P0093: Fuel system large leak detected
The engine control unit has detected a significant drop in fuel pressure, indicating a large leak in the fuel system.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Check engine light on
- Strong smell of fuel
- Poor fuel economy
- Engine misfires
- Reduced engine performance
Common causes
- Fuel line leak
- Injector leak
- Pressure-control valve fault
- Fuel rail damage
- Faulty fuel pump
How to check it yourself
- Visually inspect for fuel leaks under the car
- Check fuel lines and connections for damage
- Inspect injectors for leaks
- Test fuel pressure with a gauge
- Examine the pressure-control valve
Can I keep driving?
Do not drive the car if there is a smell of fuel or visible fuel leak.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer