P2371 — Fuel Volume Regulator B Control Circuit Performance
The ECU sees implausible feedback on the control loop for fuel volume regulator B - duty cycle does not match measured rail pressure response. The regulator either reacts too slowly, sticks, or has shifted from its calibration.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Fuel volume regulator b
- High pressure pump b
- Fuel rail
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Regulator stem sticking due to debris or wear
- High-pressure pump wear changes regulator response
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
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.