Fuel Delivery, Checking

Fuel Delivery, Checking

Special tools, testers and auxiliary items required

• Hand held remote control (jumper).

• Multimeter.

• Electrical connector test lead set.

• Fuel pressure test set (high pressure).

• Measuring container, fuel-resistant.

Test conditions

• Battery voltage 12.5 V

• Fuel filter OK

• Fuel tank at least 1/4 filled.

• Fuel pressure regulator OK.

• Ignition switched off.

Test procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check.

Start diagnosis

- Remove the fuel filler cap from fuel filler tube.

- Remove rear seat bench.

- Remove cover retainers - arrows - from the right sealing flange.





- Disconnect the electrical harness connector - arrow - from the fuel delivery unit.





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

- Connect a jumper cable from an Electrical connector test lead set to terminal - 5 - of the fuel delivery unit and to vehicle Ground (GND).






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

- Disconnect fuel line - arrow - by pulling release button.





- Connect the Fuel pressure test set (high pressure) onto the disconnected fuel supply line.





- Connect an assisting hose - arrow - on to the Fuel pressure test set (high pressure) and hold it into a measuring container.

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

- Generate pressure in the fuel system by pressing the remote control switch and slowly closing the pressure gauge shut-off valve.

• Specification: 4 bar positive pressure.

- From this point on do not move position of shut-off valve.

- Empty the measuring container.

- Press switch on remote control for 15 seconds.

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





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

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

• Fuel lines pinched.

• Fuel filter clogged.

• Fuel pump faulty.

Assembly is performed in reverse order of removal.

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Monitors, Trips, Drive Cycles and Readiness Codes.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

End of diagnosis