P0002: Fuel Volume Regulator Control Circuit Range/Performance (Meaning, Causes, Fixes)
What P0002 means
Vehicles with high-pressure fuel systems (common rail diesels and, according to OBD-Codes.com, gasoline direct injection engines) use a high-pressure pump with a fuel volume regulator that controls fuel pressure at the rail. RepairPal describes the regulator as the part that lets the fuel system release excess fuel back to the tank. P0002 sets when the engine computer (PCM) determines the regulator is not performing properly; OBD-Codes.com describes it as an electrical reading in the regulator system that is outside normal parameters. OBD-Codes.com says P0002 is not a very common code and is seen more often on diesel and GDI engines. It is a generic OBD2 code, so exact repair steps vary by make and model. Related codes are P0001 (circuit open), P0003 (circuit low) and P0004 (circuit high).
Severity: can I keep driving?
Stop and fix promptly
RepairPal rates P0002 urgent, meaning it should be dealt with right away. OBD-Codes.com gives no rating, but lists a no-start and limp mode (reduced power) among the symptoms, and RepairPal says the engine may stall. Get it diagnosed soon and avoid relying on the vehicle until it is fixed.
Common symptoms
- Check engine light on (OBD-Codes.com)
- Decreased engine performance or lack of power (both sources)
- Limp mode (reduced power) (OBD-Codes.com)
- Engine may not start (OBD-Codes.com) or may stall (RepairPal)
- Increased fuel consumption (RepairPal)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Failed fuel volume regulator solenoid (both sources)
- Wiring or connector problem in the regulator circuit, such as a short or corrosion (both sources)
- Engine computer (PCM) problem, less likely (RepairPal)
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Check for technical service bulletins (TSBs) for your year, make and model, which can point straight to a known fix (OBD-Codes.com).
- Visually inspect the wiring and connectors at the fuel volume regulator for broken wires, corrosion or loose connections, and repair what you find (OBD-Codes.com).
- Do not apply battery voltage directly to the regulator wires; OBD-Codes.com warns this can damage the system.
- Check for other stored codes, especially P0001, P0003, P0004 or fuel rail pressure codes such as P0087 to P0093, which help narrow down the fault.
Typical fixes
- Repair shorted or corroded regulator wiring or connectors (both sources)
- Replace the fuel volume regulator if it fails testing (both sources); on many engines it is part of or mounted on the high-pressure pump, so check the service manual for your vehicle
- RepairPal lists fuel pump replacement as the common repair, which fits engines where the regulator is built into the high-pressure pump
- Suspect the PCM only after the regulator and its circuit check out (RepairPal)
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- Following the factory service manual's troubleshooting steps for the specific engine (OBD-Codes.com)
- Checking the regulator's two wires back to the PCM for shorts, opens and resistance using the factory wiring diagram
- Comparing commanded and actual fuel rail pressure with a scan tool
- PCM testing or replacement if everything else checks out
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Can I keep driving with P0002?
It is not a good idea. RepairPal rates P0002 urgent and says the engine may stall, and OBD-Codes.com lists limp mode, lack of power and a no-start as possible symptoms. Get it diagnosed soon.
What is the fuel volume regulator?
It is a solenoid-controlled valve, usually on the high-pressure fuel pump, that the engine computer uses to control fuel pressure at the rail. RepairPal describes it as letting excess fuel go back to the tank. P0002 means it, or its circuit, is not performing within the expected range.
How is P0002 different from P0001, P0003 and P0004?
All four are fuel volume regulator control circuit codes. P0001 points to an open circuit, P0002 to a range or performance problem, P0003 to a circuit reading low and P0004 to a circuit reading high.
Do the sources agree on the details?
Mostly. Both name a failed regulator and wiring as causes. OBD-Codes.com describes P0002 as an electrical reading outside normal parameters, while RepairPal says the PCM has decided the regulator is not performing properly. RepairPal also lists the PCM as a cause, adds stalling and higher fuel use as symptoms, and names fuel pump replacement as the common repair, which OBD-Codes.com does not mention. RepairPal rates it urgent; OBD-Codes.com gives no severity rating. Neither source gives a repair cost.
Sources
Last reviewed 2026-10-24. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.