Fuel Pressure Regulator
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 1997 BMW Z3, 1997 BMW 840Ci, 1997 BMW 740iL, 1997 BMW 740i, and 1997 BMW 540i. However, it is still accessible from the selected car via links, so may be relevant.
- Remove fuel pressure regulator. See REMOVE/INSTALL & OVERHAUL article ENGINE PERFORMANCE section. Note code number and nominal pressure on fuel pressure regulator body. Install BMW Service Tester (133060) with connecting hose (133064) in fuel feed left line.
- Remove fuel pump relay. See DME & FUEL PUMP RELAY LOCATION table. Connect jumper wire between relay base terminals No. 30 and 87. Read off fuel injection pressure on pressure gauge.
- If fuel pressure drops rapidly, seal return line (upper line) with Clamp (133010) and briefly operate fuel pump. If injection pressure in now stable, pressure regulator is defective. If injection pressure drops, check for leak in front of pressure regulator.