Operation CHARM: Car repair manuals for everyone.

Fuel Pump Delivery Quantity, Checking






Fuel Pump Delivery Quantity, Checking

Special tools, testers and auxiliary items required

• Hand held remote control (jumper).

• Multimeter.

• Electrical connector test lead set.

• Pressure gauge (High pressure)

• Measuring container (fuel resistant).

Test conditions

• Battery voltage at least 12.5 V.

• The fuel filter OK

• Fuse (S228) OK.

• Fuel Pump (FP) Control Module (J538) OK. Refer to Fuel Injection and Ignition Repair Information.

• Fuel tank at least 1/4 filled.

• The ignition switched off.

Test sequence

- Remove the rear seat bench Refer to Body Interior Repair Information.

- Remove the right locking flange cover and bolts- arrows -.





- Disconnect the electrical harness connector - arrow - at the right locking flange.





- Connect a Hand held remote control (jumper) to terminal - 1 - of the fuel delivery unit and to vehicle battery (+).

- Connect a jumper cable from a Electrical connector test lead set to terminal - 4 - of the fuel delivery unit and to vehicle Ground (GND).





- Remove the fuel filler cap.

- Remove the rear engine cover - arrows -.





CAUTION!
The fuel system is under pressure! Before opening system, place rags around the connection area. Then release pressure by carefully loosening the connection.

- Disconnect the fuel line - arrow -.





- Connect a Pressure gauge (High pressure) to the fuel line.

- Connect the extension hose - arrow - to the pressure gauge and hold it in a measuring container.

- Open the pressure gauge shut-off valve. The lever points in the direction of flow.

- Create fuel system pressure by pressing the switch on the Hand held remote control (jumper) in and slowly closing the shut-off valve of the pressure gauge.

- Pump the fuel into the





• Specification: 4 bar positive pressure.

- Do not move the position of the shut-off valve.

- Empty the measuring container.

- Press the switch on the Hand held remote control (jumper) in for 15 seconds.





- Compare the quantity of fuel delivered with the minimum delivery rate in the diagram (cm3/15s).

• Voltage at the fuel pump with the engine stopped and the pump running is approx. 2 volts less than the battery voltage.

If the minimum delivery quantity is not obtained, the following malfunctions may be present:

• Fuel lines pinched.

• Fuel filter clogged.

• Fuel pump faulty.

Installation

- Connect the fuel line - arrow -.





- Install the rear engine cover - arrows -.





- Connect the electrical harness connector - arrow - at the right locking flange.





- Install the right locking flange cover and bolts- arrows -.





- install the rear seat bench Refer to Body Interior Repair Information.

Torque specifications