The P0004 code is analogous with the electrical circuit. It connects to our fuel system and is generally found in diesel engines. The other codes which might be related to it are P0006 and P0007. It is a generic OBD-II Code which indicates and issue with the engine control module which is not able to read signals.

There can be some sort of corrosion in the sensor connector

A broken wire to the Electronic Control Module

Defects in the fuel shutoff valve

Damaged ECM

Some faults in the FVCV circuit

Problem with the PCM

Replace/Repair These Parts To Fix OBD Code P0004

Engine Control Module - OBD Code P0004 can flash if the engine control module is damaged.

The first and foremost task is to do diagnosis by visually inspecting all wiring and connectors

Look if there are some shorted or burned wirings and then you must replace circuitry and connectors as per the requirement

If the system wiring, connectors, and components appear to be in normal working order, connect the scanner to the diagnostic connector and record all stored trouble codes and freeze frame data

You can easily diagnose the conditions which have helped to this code with the help of this information

Now once the codes are fully cleared up, carefully operate your car to check if the code returns or not

There are chances that if you may have an intermittent condition that the code would fail to return

It is very important to test the sensor voltage as per your vehicle make and model specifications

You must test your fuel volume control regulator by checking resistance after it has been unplugged from the PCM harness

Replace the Powertrain Control Module only after checking that the code actually exists and after exhausting all other possibilities