Fuel Pump (FP) delivery quantity, checking

WARNING: This page is about a different car, the 2006 Audi A4, 2005 Audi A4, 2004 Audi A4, 2003 Audi A4, and 2002 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

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 sequence

Remove the fuel filler cap from fuel filler tube.
Remove rear seat bench →
- 72 - SEAT - FRAMES
- 72 - SEAT - FRAMES for BODY INTERIOR - CABRIOLET
.

Fig 1: Identifying Right Sealing Flange Cover Retainers

GW00005163

Courtesy of VOLKSWAGEN UNITED STATES, INC.

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

Fig 2: Disconnecting Electrical Harness Connector From Fuel Delivery Unit

GW00018689

Courtesy of VOLKSWAGEN UNITED STATES, INC.

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 (+).

Fig 3: Connecting Jumper Cable From Electrical Connector Test Lead Set To Terminal 5 Of Fuel Delivery Unit And To Vehicle Ground (GND)

GW00001012

Courtesy of VOLKSWAGEN UNITED STATES, INC.

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

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

Fig 4: Disconnecting Fuel Return Line By Pressing Release Buttons

GW00018690

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Disconnect the fuel return line - arrow - by pressing release buttons.

Fig 5: Fuel Line From The High Pressure Fuel Gauge Connected To The Disconnected Fuel Return Line

GW00001156

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Connect a fuel line from the Fuel pressure test set (high pressure) to the disconnected fuel return line and hold it in the measuring container.
Press the switch on the Hand held remote control (jumper) and operate the fuel pump for 15 seconds.

Fig 6: Delivery Rate Diagram

GW00005165

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Compare quantity of fuel delivered with minimum delivery rate in the diagram (cm ³ /15s).

NOTE:

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 plugged.
Fuel pump faulty.

If necessary, repair any pinched or plugged lines.
Replace the fuel filter. Refer to → 20 - FUEL SUPPLY SYSTEM .
Replace the fuel pump. Refer to → 20 - FUEL SUPPLY SYSTEM .

Assembly is performed in reverse order of removal. Note the following:

Install the rear seat bench →
- 72 - SEAT - FRAMES
- 72 - SEAT - FRAMES for BODY INTERIOR - CABRIOLET
.

Final procedures

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

Check the DTC memory.
If necessary, erase the DTC memory. Refer to Diagnostic Mode 04: Reset/delete diagnostic data .
If the DTC memory was erased, generate readiness code. Refer to Readiness Code .

End of diagnosis.