Fault codeP0087

MODERATE

Fuel Rail/System Pressure - Too Low

What this code means

Fuel Rail/System Pressure - Too Low.

P0087 is a generic code: it means the same thing on every make. P0087 belongs to family P00xx — Fuel and air metering, auxiliary emission controls. Its page explains how to read a code and groups all its codes by part.

Fuel pressure regulation

On direct-injection petrol and common-rail diesel engines, a high-pressure pump feeds the injectors through a rail. The control unit regulates the pressure with a valve on the pump (volume or metering regulator) and/or a valve on the rail, and checks the result with the rail pressure sensor.

Symptoms

Clear loss of power, especially under load or uphill, engine coughing or stalling, limp mode, long starting. Common on common-rail diesels: the control unit commands an injection pressure and the pump cannot reach it.

Common causes

Clogged fuel filter — the first thing to change
Worn high-pressure pump, or tired lift pump in the tank
Faulty pressure regulator or pump metering valve
Injector with excessive return leakage, dropping the rail pressure
Air getting into the low-pressure circuit, porous hose, tank nearly empty

How to diagnose it

Replace the fuel filter if it has done more than 30,000 km: it is cheap, and it is the most common cause. In live data, compare the requested rail pressure with the measured pressure: the gap grows with load when the pump is weakening.

On diesels, an injector leak-off test — measuring the volume each injector returns — names the one that is leaking. Also check the low-pressure circuit for air bubbles in the clear hose, if there is one.

Watch it live in Klaro

With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:

Fuel rail pressure (absolute)
Fuel rail absolute pressure
Fuel pressure

What to do

Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.

Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →

Repair cost

Fuel filter: €20 to €80. Pressure regulator: €80 to €250. Diesel injector: €200 to €600 each. High-pressure pump: €500 to €1,500 fitted.

How to read this code

PPowertrain
0standardised code
0Fuel and air metering, auxiliary emission controls
87P0087