Fuel Pressure: Testing and Inspection

Checking residual pressure

NOTE: For information regarding fuel pressure while running, see Fuel Pressure Regulator. Fuel Pressure Regulator

WARNING: Checking residual pressure involves partial dismantling of the car's fuel system. The following points must therefore be observed in connection with this work:
- Work only in a well-ventilated area. If approved equipment for the extraction of fuel vapours is available, be sure to use it.
- Wear suitable gloves. Prolonged contact with fuel can cause skin irritation or dermatitis.
- Keep a class BE tire extinguisher near at hand. Be mindful of the danger of sparks caused by short circuits and when connecting and disconnecting leads in electrical circuits.
- No smoking anywhere in the vicinity,
- Wear protective goggles.





1 Remove the valve cap. Connect the pressure gauge equipment, tool 83 93 852, and tool 83 94 744. Secure tool 83 94 744 to the fuel rail, "safety catch" on. Tool "safety catch" off.





2 Connect tool 83 93 886 between fuse No. 8 and fuse No. 19.
3 Run the pump manually until the pressure gauge no longer rises. Turn off the pump. Residual pressure after 20 minutes should be at least 2.3 bar (33 psi).
4 Note the pressure gauge reading.
5 Remove tool 8393886 and refit the fuses, No. 8(15 A) and No. 19 (20 A).