P2400 to P2422 and P2024 to P2028: EVAP leak detection pump, fuel cap sensor, valves and vapour temperature
In the system that stores fuel vapour, the leak detection pump or its sense circuit, the fuel cap sensor, the switching valve or the vent valve has a fault, or the fuel vapour temperature sensor reads wrong.
SeverityLowLittle risk to the car, but the fault stays until it is repaired.
Can you keep driving?Safe to drive, book a checkWhat does P2400 mean?
Some cars test the fuel vapour system for leaks by pumping a little air into it or pulling a vacuum with a small electric pump, then watching how the pressure holds. A sensor at the filler tells the computer whether the cap is closed, and on some cars it lights a reminder. A vapour temperature sensor helps it judge the readings. When one of these parts fails, the computer cannot complete its leak test, so the warning light comes on, but the engine runs normally.
What causes P2400?
- A leak detection pump that has failed or taken in water
- A fuel cap left loose, or a cap sensor at the filler that fails
- A vent valve stuck open or closed by dirt
- A damaged wire or connector near the tank or canister
- A failed vapour temperature sensor
What to check first for P2400
- Check that the fuel cap is closed and clicks, and that its seal is intact
- Inspect the leak detection pump and the vent valve near the canister for dirt and water
- Inspect the wiring under the car near the tank
- Have the leak detection test run with a scan tool
Can you drive with P2400?
You can drive safely. The car may fail an emissions test until it is repaired; if you smell fuel strongly, have it looked at soon.
Since May 2018 an engine warning light that stays on is a major defect at the MOT, so the car fails until the fault is fixed.
Codes on this page
23
- P2024Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Circuit
- P2025Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Performance
- P2026Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Circuit Low Voltage
- P2027Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Circuit High Voltage
- P2028Evaporative Emissions (EVAP) Fuel Vapor Temperature Sensor Circuit Intermittent
- P2400Evaporative Emission System Leak Detection Pump Control Circuit/Open
- P2401Evaporative Emission System Leak Detection Pump Control Circuit Low
- P2402Evaporative Emission System Leak Detection Pump Control Circuit High
- P2403Evaporative Emission System Leak Detection Pump Sense Circuit/Open
- P2404Evaporative Emission System Leak Detection Pump Sense Circuit Range/Performance
- P2405Evaporative Emission System Leak Detection Pump Sense Circuit Low
- P2406Evaporative Emission System Leak Detection Pump Sense Circuit High
- P2407Evaporative Emission System Leak Detection Pump Sense Circuit Intermittent/Erratic
- P2408Fuel Cap Sensor/Switch Circuit
- P2409Fuel Cap Sensor/Switch Circuit Range/Performance
- P2410Fuel Cap Sensor/Switch Circuit Low
- P2411Fuel Cap Sensor/Switch Circuit High
- P2412Fuel Cap Sensor/Switch Circuit Intermittent/Erratic
- P2418Evaporative Emission System Switching Valve Control Circuit/Open
- P2419Evaporative Emission System Switching Valve Control Circuit Low
- P2420Evaporative Emission System Switching Valve Control Circuit High
- P2421Evaporative Emission System Vent Valve Stuck Open
- P2422Evaporative Emission System Vent Valve Stuck Closed
Related codes
Checked on · Rafael Soares
These are the generic meanings every manufacturer shares. Each brand adds its own detail, so your car's handbook, its service information and a qualified mechanic have the last word. OdoKeep has no connection with any manufacturer, and the app does not read codes from the car.
