P0088 fault code: what it means

P0088: Fuel rail pressure is higher than it should be.

Engine and gearbox (powertrain) · Costly if missed

Usual causes, most likely first

faulty fuel rail pressure sensor
sticking pressure regulator or pressure control valve
faulty fuel metering valve on the diesel pump
wiring fault at the regulator

P0088 by make

Audi

Fuel rail pressure higher than it should be. Often a sensor or regulator valve fault; on some 3.6 V6 petrols, a stretched timing chain.

Usual causes: faulty rail pressure sensor (G247) or wiring; fuel pressure regulator valve (N276) fault; fuel metering valve (N290) fault; stretched timing chain (3.6 V6)

BMW

Fuel rail pressure too high. On BMW direct injection or common-rail diesel the pressure control is not working.

Usual causes: high pressure pump control valve sticking; rail pressure sensor fault; pressure regulator fault

Ford

Fuel rail pressure too high: the engine computer sees more pressure than it asked for. A known 3.2 TDCi Ranger fault, can cause idle hunting.

Usual causes: sticking suction control valve (SCV) on the high-pressure pump; fuel rail pressure sensor reading wrong; contaminated fuel wearing the SCV

GWM

Fuel rail pressure too high (diesel).

Usual causes: fuel metering/pressure control valve sticking; rail pressure sensor; restricted return

Isuzu

Fuel rail pressure too high. On 4JJ1 often the SCV sticking or the pressure limiter.

Usual causes: sticking suction control valve (SCV); fuel rail pressure sensor; pressure limiter valve

Jeep

Fuel rail pressure too high on CRD diesels.

Usual causes: fuel pressure regulator stuck; rail pressure sensor; restricted return line

LDV

Fuel rail pressure too high (diesel).

Usual causes: pressure control/metering valve sticking; rail pressure sensor; restricted return

Mazda

Mazda meaning differs by engine. Petrol SkyActiv-G: fuel pressure sensor reading off target. Diesel SkyActiv-D: common rail pressure too high.

Usual causes: ran out of fuel / air in fuel line (petrol); fuel pressure sensor; high-pressure pump relief valve or suction control valve; blocked fuel filter (diesel)

Mercedes-Benz

Fuel rail pressure too high (diesel).

Usual causes: faulty pressure regulator; faulty rail pressure sensor

Mini

Fuel rail pressure too high (direct injection Cooper S or diesel).

Usual causes: high pressure pump control valve sticking; rail pressure sensor; pressure regulator fault

Mitsubishi

Common-rail fuel pressure too high (4N15 / 4D56). Usually the suction control valve sticking and over-feeding the rail.

Usual causes: sticking or contaminated suction control valve (SCV); faulty rail pressure sensor; rail pressure limiter fault

Nissan

Diesel fuel rail pressure too high (YD25 common rail).

Usual causes: suction control valve (SCV) fault; rail pressure sensor fault; rail pressure relief valve fault; wiring fault

Skoda

Fuel rail pressure higher than it should be. Often a sensor or regulator valve fault; on some 3.6 V6 petrols, a stretched timing chain.

Usual causes: faulty rail pressure sensor (G247) or wiring; fuel pressure regulator valve (N276) fault; fuel metering valve (N290) fault; stretched timing chain (3.6 V6)

Subaru

Fuel rail pressure too high on FA20DIT direct-injected engines.

Usual causes: faulty high-pressure fuel pump control valve; faulty rail pressure sensor; ECU software

Toyota

Diesel common-rail pressure too high (D-4D): rail pressure has gone over the limit the ECM allows.

Usual causes: suction control valve (SCV) stuck open; SCV wiring fault; pressure limiter/discharge valve fault; rail pressure sensor fault

Volkswagen

Fuel rail pressure higher than it should be. Often a sensor or regulator valve fault; on some 3.6 V6 petrols, a stretched timing chain.

Usual causes: faulty rail pressure sensor (G247) or wiring; fuel pressure regulator valve (N276) fault; fuel metering valve (N290) fault; stretched timing chain (3.6 V6)

Volvo

Fuel rail pressure too high (diesel).

Usual causes: fuel pressure regulator; rail pressure sensor; restricted return

What the repair usually costs

CVT valve body replacement (remanufactured, in car)NZ$1,280–NZ$2,420 · A$1,200–A$2,400
A/C compressor replace incl. drier and flush (European)NZ$1,560–NZ$3,200 · A$1,490–A$3,050
Parking sensor replace, one sensorNZ$130–NZ$520 · A$130–A$510
Timing chain, tensioner and guides (4-cylinder)NZ$1,120–NZ$2,530 · A$1,160–A$2,570

Not sure what P0088 means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.