Fuel Pressure

Before disconnecting, cover fuel line connector using shop towel to absorb any fuel spray. Connect Fuel Pressure Gauge (5011) between fuel line and fuel rail. Seal free end of hose using Plug (5266) or use Fuel Drainage Unit (981 2270, 2273 and 2282).
Remove fuel pump relay. Connect a jumper wire between relay terminals No. 1 and 3. See Fig 1. Turn ignition on. Fuel pump should start. Fuel filler cover can be removed to determine whether main pump is operating. Check fuel pressure. See FUEL PRESSURE SPECIFICATIONS (C/S/V70) table. If pressure is not to specification, replace pressure sensor.
To check fuel system residual pressure, turn ignition off. Disconnect jumper wire between relay terminals. Reinstall fuel pump relay. System pressure should not drop below specification in less than 20 minutes. See FUEL PRESSURE SPECIFICATIONS (C/S/V70) table. If pressure is not to specification, check injectors, connections, and fuel pump non-return valve or lines. Repair as necessary.

Fig 1: Identifying Fuel Pump Relay Terminals

Courtesy of VOLVO CARS OF NORTH AMERICA.

FUEL PRESSURE SPECIFICATIONS (C/S/V70

Application ⁽¹⁾

psi (kPa)

Key On, Engine Off Fuel Pressure

C/S/V70

43.5 (300)

Running Pressure

Non-Turbo

30-45 (210-310)

Turbo

30-55 (210-380)

Residual Fuel Pressure⁽²⁾

29 (200)

⁽¹⁾	On engines without fuel return line on fuel rail, fuel pressure regulator is mounted under rear of vehicle, near fuel tank.

⁽²⁾	Minimum pressure 20 minutes after engine is shut down.