Diagnostic Trouble Code (DTC) P0087 deciphered as “Fuel Rail/System Pressure Too Low”. This error is detected by the PCM when the pressure in the fuel rail or the whole fuel system drops below the minimum allowable level required to supply the engine with a sufficient amount of fuel for operation.
P0087 code — What Does It Mean?
The pressure in the fuel line varies constantly depending on the engine's fuel demand. These changes are tracked by a sensor in the fuel rail. The code P0087 is stored in the ECU memory when the ramp pressure is 250MPa lower than the minimum value for 2 seconds. As soon as this happens the PCM turns on the engine warning light and activates the failsafe mode regardless of the cause.
What are the Common Symptoms of the P0087 Code?
In addition to the check indicator on the dashboard, the presence of such a problem with the fuel system will be indicated by a number of symptoms of typical vehicle behavior. The main one is a noticeable loss of power during acceleration. In some cases, when starting the engine revolutions will float, up to the motor stop, and sometimes the problem will not bother until you do not put much pressure on the gas pedal. Quite often, the Fuel Rail/System Pressure — Too Low error occurs only at rpm above 3,000.
Causes of Fuel Rail/System Too Low Pressure Error
Error P0087 in the VCDS diagnostic program
A number of elements in the fuel system may affect the deterioration of fuel supply and consequently cause the P0087 code. Therefore, when you are asked what causes low fuel rail pressure, the answer may be:
- Fuel filter clogging (both fine and coarse mesh).
- Failure of the fuel pump in the tank (reduced capacity).
- A faulty fuel pressure sensor or failure of its readings.
- Defective pressure control valve in the fuel line.
- Clogged fuel injectors (not holding pressure).
- In GDI and Common Rail systems, it may be high pressure pump wear (worn solenoid).
How do you diagnose code P0087?
It is worth starting with pressure gauge test in the low pressure and high pressure lines at different engine operation modes, as well as with the fuel pump, located in the tank. Quite often the unstable operation of the fuel system is caused by a bad contact in the connector of the fuel station or clogging of the filter, and consequently by the complication of the fuel passage.
Pressure gauge test in the low pressure and high pressure lines
The following things should be checked:
- low-pressure line;
- high-pressure line;
- pressure regulator valve;
- fuel injectors;
- connectors and electrical harnesses;
- fuel system pressure gauge;
- high-pressure fuel pump.
In searching for the cause of pressure loss in the fuel system on different cars such as Audi, Citroen, Ford, Kia and Hyundai pay attention to the features of their fuel systems. Often there are the most likely problems based on the weaknesses of the car brands. In some, it is wiring on the pump in the tank, in others the pressure regulator on the fuel injection pump, and in some others, just the injector does not hold pressure and pours into the return.
Troubleshooting the P0087 code: video
Note that there is no single solution to the problem, if one car will help replace the pressure regulator, it will be useless on the other.
It is necessary to consistently find out the exact cause, but in general, most often the error P0087 will help to eliminate:
- Replacing the fuel filter or screen.
- Replacing the fuel pump.
- Replacing the fuel pressure sensor.