Fuel and air

P0002 — Fuel Volume Regulator Control Circuit Range/Performance

Severity: medium Drive with care, to a shop

What P0002 means

The engine control module uses a fuel volume regulator to meter how much fuel reaches the high-pressure fuel pump. P0002 is set when the control signal or the regulator's response falls outside the expected range, or when actual fuel pressure does not match the target. It is most common on diesel and direct-injection engines.

Symptoms

  • Check Engine light on
  • Rough or unstable idle
  • Loss of power or hesitation on acceleration
  • Stalling or no-start
  • Long cranking, especially when warm
  • Worse fuel economy

Possible causes

  1. Failed fuel volume regulator (solenoid)
  2. Damaged wiring or corroded connector in the regulator circuit
  3. Weak low-pressure fuel pump or low supply pressure
  4. Clogged fuel filter
  5. Leaking or sticking valve in the high-pressure system
  6. ECM fault (rare)

How to diagnose

  1. Scan for codes and freeze-frame data, and look for related fuel pressure codes
  2. Inspect the regulator connector and harness for corrosion, chafing or moisture
  3. Measure regulator coil resistance and compare it with the manufacturer's spec
  4. Check power, ground and the control signal from the ECM at the connector
  5. Test low-pressure supply pressure and volume
  6. Compare commanded and actual rail pressure at cranking, idle and under load
  7. Check the fuel filter and replace it if it is restricted
  8. Measure injector return flow where the design allows it

Common fixes

  • Replace the fuel volume regulator
  • Repair or replace damaged wiring and connectors
  • Replace the fuel filter
  • Replace the low- or high-pressure fuel pump if it is faulty
  • Reprogram or replace the ECM only after confirming it is at fault

Questions and answers

What does code P0002 mean?

It is a fault in the fuel volume regulator control circuit. The ECM sees the regulator not performing as commanded, so fuel delivery or pressure can drift from the target.

Can I drive with P0002?

Only briefly and carefully, such as to a shop. The engine can lose power or stall while driving, so do not put off diagnosis.

What should I check first for P0002?

Start with the regulator wiring and connector, then check low-pressure fuel supply and the fuel filter. If those are fine, test the regulator itself.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.