Fuel Pump: Testing and Inspection

Checking Quantity Delivered By Fuel Pump

Tools







Preliminary work

INFORMATION: The battery voltage must not fall below 12.5 volts during the fuel delivery rate check.

1. Check the battery charge state using a voltmeter or the Porsche PIWIS Tester 9718 (Supply voltage menu item).
2. PIWIS Tester 9718 with the adapter line must be connected to the input socket in the vehicle. Switch on ignition and switch off all loads (radio, air conditioning, etc.).
3. Remove the cover for the rear and centre underbody.

Checking delivery rate







1. Attach or mount a warning sign in a clearly visible position on the vehicle.

DANGER:
Working on the fuel system.
- Danger of fatal injury and damage to property.

- Safety instructions must be observed at all times fuel system.







2. Disconnect the rapid-action coupling on the fuel return line -1- by pressing in the locking lug -arrow- and pulling off the line. Soak up emerging residual fuel using a clean cloth.







3. Insert the flat connector (Original Porsche spare part with Part No. 996.106.255.00) with the O-ring side into the open end of the hose for the special tool connection hose 9507 and secure with a screw-type clamp.
3.1. Fit flat connector (connection diameter: 8 mm) with hose into the coupling connection on the return line. Make sure the coupling is fitted correctly and securely (it must click into place) by pulling the line apart.







3.2. An adapter line with a connection diameter of 8 mm from the Test case WE1291: K-Jetronic Tester V.A.G. 1318 can also be used instead of the Porsche flat connector.

4. Put the open end of the hose in a petrol-resistant canister. Have a stopwatch ready for the following measurement.
5. Switch on the Porsche PIWIS Tester 9718, select Diagnosis and then highlight the vehicle 911 (997).

INFORMATION:
- The fuel system of the 997 Turbo, 997 GT2 and 997 GT3 has two electric fuel pumps (EKP).
- The delivery rate volume and supply pressure of these pumps must be checked individually.







- These can be activated individually in the PIWIS Tester 9718.







6. Run the individual control unit search for DME. To do this, select DME with the tracer pen and press F12>>.
7. Select the Drive links item and then select fuel pump relay 1 with the tracer pen.







7.1. Press F8=Start to activate fuel pump 1 (EKP 1) for 30 seconds.







8. Switch off the fuel pump after 30 seconds by pressing F8=Stop.
9. Pour the collected fuel into a suitable measuring container and compare the actual quantity delivered with the required quantity.
- Required value for quantity of fuel delivered by fuel pump 1:
>> in 30 seconds, at least 1.1 litres << 1)

10. Repeat the process for fuel pump 2 (EKP 2).
10.1. Proceed as described for fuel pump 1: Activate fuel pump relay 2 using the PIWIS Tester 9718.
- Required value for quantity of fuel delivered by fuel pump 2:
>> in 30 seconds, at least 1.5 litres << 1)

11. Disconnect flat connector with hose and connect the rapid-action coupling to the fuel return line. Make sure the coupling is fitted correctly and securely (it must click into place) by pulling the line apart.

1) The specified values are minimum quantities. If the supply voltage is significantly higher than 12 volts (e.g. 13.5 volts), the fuel pumps will deliver more fuel.

Subsequent work

1. Switch off ignition, switch off Porsche System Tester and disconnect adapter line in the passenger compartment.
2. Install the cover for the rear and centre underbody.