Fuel Pressure
WARNING: This page is about a different car, the 1997 Volvo 960. However, it is still accessible from the selected car via links, so may be relevant.
- 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. Fuel pressure should be about 43.5 psi (3.0 kg/cm2 ). 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 29 psi (2.0 kg/cm2 ) in less than 20 minutes. If pressure is not to specification, check injectors, connections, and fuel pump non-return valve or lines. Repair as necessary.