Delivery Rate, Checking

Diagnostic Procedures

Delivery Rate, Checking

CAUTION!
Fuel supply line is under high pressure! Wear protective goggles and protective clothing to prevent injuries and contact with skin. Before removing from hose connection consult the Repair Information for proper procedure.

Test procedure

- Observe safety precautions. Refer to => [ Safety Precautions ] Safety Precautions

- Observe Clean Working Conditions. Refer to => [ Clean Working Conditions ] Clean Working Conditions

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

- Remove high pressure in fuel system.

Test sequence

- Read safety precautions before beginning work => [ Safety Precautions ] Safety Precautions.

- Observe Clean Working Conditions.=> [ Clean Working Conditions ] Clean Working Conditions

• A second technician is needed for the following task.

- Connect pressure gauge with adapter.

- However, do not connect ends of Hose to fuel rail connector.

- Hold the end of the hose in a measuring container.





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

- Switch ignition on.

- Operate hand held remote (jumper). Slowly close shut off tap, until pressure gauge shows 4 bar fuel pressure. From this point on do not move position of shut off tap.

- Release hand held remote (jumper) switch.

- Empty measuring container.

- Operate remote control for 15 seconds.

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





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

If minimum delivery rate is not attained:

- Check fuel lines for possible restrictions (kinks) or blockages.

If lines are OK:

- Replace fuel filter.

- Repeat test.

If specified value is again not obtained:

- Fuel Pump faulty, replace fuel delivery unit.

If delivery rate has been attained but you suspect a fuel supply system malfunction (e.g. intermittent failure of fuel supply system)

- Check Fuel Pump current draw.