P2A40
Alternative Fuel System - Injector Leakage to Rail Detected
The AFCM detects pressure decay in the alternative fuel rail consistent with injector leakage. Even with all injectors commanded closed, fuel flows back into the rail.
The AFCM detects pressure decay in the alternative fuel rail consistent with injector leakage. Even with all injectors commanded closed, fuel flows back into the rail.
Common causes
- high
Injector seat worn - leaks closed
One of the most commonly reported causes for this code — check this first.
Typical part cost: $440-2420
- medium
Injector seal aged - external leak path
A plausible cause — test and verify before replacing parts.
Typical part cost: $440-2420
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P2A40 mean?
P2A40 means "Alternative Fuel System - Injector Leakage to Rail Detected". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2A40?
injector seat worn - leaks closed; injector seal aged - external leak path — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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