Fault code P0087 is called “Fuel Rail/System Pressure – Too Low” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P0087
Code P0087 means that the Powertrain Control Module (PCM) has detected a fuel rail pressure that is below the minimum specifications. This error also applies to the fuel pressure sensor input voltage.
Some vehicles are equipped with a no-return fuel system, their fuel pump has pulse width modulation. The control module can change the speed of the pump to deliver fuel to the ramp. There is no regulator that returns the fuel back to the tank. The fuel ramp pressure sensor is a three wire, piezoelectric pressure sensor.
There is another fuel ramp pressure sensor design that takes into account the inlet rarefaction. Instead of monitoring the fuel ramp pressure directly, the sensor monitors the degree of rarefaction in the intake manifold. This changes the resistance of the sensor, and the PCM receives a voltage input signal.
On another type of fuel ramp pressure sensor, the fuel pressure regulator is built in. It does not affect the fuel pressure regulation, but it can be electronically regulated. Even if the regulator and sensor are integrated, the regulator can also operate under vacuum.
The voltage from the fuel ramp pressure sensor is taken by the PCM, which regulates the fuel pump voltage. This is done to achieve the desired fuel ramp pressure, which contributes to more efficient fuel consumption.
If the fuel ramp pressure is lower than the value programmed in the PCM, error code P0087 will be stored. After that, the malfunction indicator on the instrument panel will illuminate to signal the problem.
Symptoms of vehicle malfunctions
The main signal that an error P0087 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- The “Check engine” control lamp on the control panel will illuminate (the code will be memorized as a fault).
- Other related trouble codes may also be present, such as engine misfire and idle control.
- Poor starting, especially when the engine is cold.
- Floating revolutions, and attempts to stall at idle.
- Increased fuel consumption.
- Reduced power output of the engine.
- Black smoke coming out of the exhaust pipe.
Code P0087 is quite serious, it is recommended to eliminate it as soon as possible. Because low fuel pressure can lead to a wide range of drivability problems and cause internal engine damage.
Factors that can cause this error code
The error code P0087 can mean that one or more of the following problems have occurred:
- Faulty fuel pressure regulator.
- Clogged fuel filter or screen.
- Fuel pump may be damaged.
- Defective fuel pump drive module.
- Short-circuited, broken wiring or connectors in wiring harness to fuel rail pressure sensor.
- Damaged fuel line.
- Incorrect fuel ramp pressure sensor (FRP) reading.
- Sometimes faulty PCM is the cause.
How to fix or reset OBD-2 code P0087
Some suggested steps for troubleshooting and fix the error code P0087:
- Connect the scan tool to the vehicle’s diagnostic port to retrieve the stored codes.
- Clear the error codes from the memory and test-drive the vehicle to see if code P0087 appears again.
- Inspect the fuel tank, including the fuel lines. Repair or replace if you find any defects.
- Replace the fuel filter.
- Disconnect the fuel pump and check its condition. Replace it if necessary.
- Check and replace the fuel rail pressure sensor (FRP) if necessary.
Diagnose and repair of problems
If the vehicle is equipped with a fuel pressure test fitting on the fuel rail or line, check the fuel pressure with a mechanical gauge. To determine if it meets the specifications. These are the first steps to be taken when the P0087 error occurs.
Fuel pressure should also be checked under load with a gear engaged or during acceleration. If the fuel pressure is lower than normal, visually inspect all fuel lines going back to the tank. Visually inspect for problems or damage, such as a bent fuel line.
The fuel filter may be clogged if it hasn’t been changed in a long time. Also, the fuel filter in the tank may be blocked or clogged. It is worth checking for damage to the fuel tank that could cause the bottom to press against the cap at the fuel pump inlet.
Vehicles equipped with a fuel pump drive module usually operate with a PWM (pulse width modulation) input signal from the PCM / ECM. And a PWM output signal for the fuel pump. In other words, they operate on a duty cycle, which is a voltage on/off time. Not a constant voltage to control the speed of the pump.
The PWM signal can be checked in the driver module using the wiring diagram. The duty cycle should change depending on the fuel pump demand set by the PCM / ECM unit.
Some vehicles, such as Ford, double the duty cycle output, so 30% of the input power will result in 60% of the output power for the fuel pump. The fuel pump duty cycle should reflect this increase.
Fuel Pressure Sensor
The fuel pressure sensor can be checked using the electrical circuitry. Typically, there is a supply voltage reference or ground wire that is monitored by the PCM. A problem with the power or ground wire usually sets a different code. Such as P0190 – fuel ramp pressure sensor circuit failure. Or P0191 – range / performance of fuel ramp pressure sensor circuit.
Excessive sensor or wire resistance can cause incorrect readings. Check the pressure sensor resistance by disconnecting the sensor and connecting the positive and negative leads to the sensor connector. If the resistance is higher than specified, replace the sensor.
You can check the wiring with a multimeter set to ohms. And also by disconnecting the sensor and PCM, checking for excessive resistance between the two wiring harness terminals with the positive wire on one end. And the negative wire at the other end of the same wire.
On which vehicles does this problem occur most frequently
Fault code P0087 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- Audi (A4, Q5, Q7)
- Chevrolet (Captiva)
- Citroen (C4, C5, DS4, Jumper, Picasso)
- Ford (C-Max, Connect, Escape, Explorer, Focus, Fusion, Galaxy, Kuga, Mondeo, S-Max, Transit)
- Hyundai (Elantra, Grand Starex, H1, Porter, Santa Fe, Starex, Terracan, Tucson, i30, ix35, ix55)
- Kia (Bongo, Carnival, Ceed, Sorento)
- Land Rover (Discovery, Freelander, Range Rover)
- Mercedes-Benz (Sprinter, Vito, W212, W221)
- Mini (Cooper)
- Nissan (Juke, Patrol, Qashqai)
- Opel (Astra, Insignia)
- Peugeot (206, 3008, 307, 308, 408, 508, Boxer, Partner)
- Skoda (Octavia, Superb)
- Toyota (Corolla, Land Cruiser)
- Volkswagen (Amarok, Caravelle, Crafter, Passat, Tiguan, Touareg, Transporter)
- Volvo (XC90)
- GAZelle (Next)
- UAZ (Patriot)
Fault code P0087 can sometimes be found with other errors. The most common are the following: P0088, P0090, P0093, P0128, P0671, P0672, P0673, P0676, P1065, P1113, P1186, P1197, P3003.