P0004 - FUEL VOLUME REGULATOR CONTROL CIRCUIT HIGH

The DTC P0004 OBDII code is related to the electrical part of the fuel volume regulator system. The automotive fuel system consists of a lot of components. Among these components, we can highlight the fuel filter, injectors, lines, and fuel pump.

The purpose of the pump is to increase the fuel pressure until it reaches a necessary pressure in the fuel rail for the injectors. These pumps have a high-pressure side and a low-pressure side. This pressure is controlled by a Fuel Volume Regulator (FVR).

If an electrical reading is detected in the controller that is above the set limit, this code will be set. Take into account this code is not commonly seen but appears in most cases on diesel or gasoline direct injection vehicles.

• The malfunctioning lamp (Check Engine) turns on.
• You may notice a lack of energy.
• The vehicle will not start.

Reasons to set the P0004 OBD2 error code:

• Possibly the fuel volume regulator solenoid has failed.
• Problems in the fuel volume regulator wiring.

To troubleshoot problems caused by the P0004 OBDII diagnostic code, try this:

• Verify Technical Service Bulletins (TSB).
• Chew all the wires and connectors that belong to the fuel volume regulator circuit and system. If some noticeable problems are found, repairs should be made.
• Change the Fuel Volume Regulator (FVR).