Alternative Fuel Rail Pressure Regulator Inlet Pressure Too High
The measured inlet pressure of the alternative fuel rail pressure regulator exceeds the calibrated maximum. Pump regulator stuck high or downstream restriction.
Affected components
- Alt fuel rail pressure regulator
- Alt fuel pump
- Afcm
Common causes
- High likelihood: Pump pressure regulator stuck high
- Medium likelihood: Restriction downstream of regulator
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.