Tandem Pump, Checking

Tandem Pump, Checking

Special tools, testers and auxiliary items required

• Tandem pump tester (VAS 5187 )

• Torque wrench (V.A.G 1331)

• Vehicle diagnostic, testing and information system ( VAS 5051) with diagnostic cable (VAS 5051/5A ) or (VAS 5051/5A)

Test Conditions

• Coolant temperature must be at least 85° C.

• Pump-Injector Unit OK.

• Fuel filter and fuel lines must not be plugged.

Procedure

- Remove the locking bolt - arrow -.





- Connect the pressure gauge (VAS 5187) as shown.





- Start engine and run at idle speed.

- Connect the vehicle diagnostic, testing and information system (VAS 5051) and select operating mode "Vehicle On-Board Diagnostics (OBD)". Then, go into control module for engine electronics with address word "01".

- Press diagnostic function "08 - Read measuring value blocks ".

- Enter display group "2" via the number keypad and confirm input by pressing the Q button.

- Read idle engine speed indicated in display field 1.

- Increase engine speed to 1500 RPM.

- Observe pressure displayed on pressure gauge.

Specified value: at least 3.5 bar

- Press the <- key.

- Press function "06 - End output".

- Switch off ignition.

If the specification is not obtained:

- Replace the tandem pump => [ Tandem Pump ] Tandem Pump.

• After removing the pressure gauge for tandem pump ( VAS 5187), tighten the plug to 25 Nm. Always replace the seal.