Tandem and Fuel Pump

Tandem and Fuel Pump

DANGER!
The tandem pump must not be disassembled under any circumstances because it can cause the vacuum part to malfunction. The result would be brake booster failure.

Special tools, testers and auxiliary items required

• Torque wrench (5 to 50 Nm) (VAG 1331)

• Spring-type clip pliers (VAS 5024 A)

Removing

• Work sequence for removing and installing tandem pump is described. Work sequence for Fuel Pump (FP) is identical up to disconnecting the vacuum line.

With Engine Code BKW

- Remove fuel filter. Refer to --> [ Fuel Filter ] Fuel Filter.

With Engine Code BWF

- Remove bypass flap with cooler for Exhaust Gas Recirculation (EGR). Refer to --> [ Bypass Flap with Cooler Assembly Overview ] .

Continuation for All

- Remove intake manifold. Refer to --> [ Intake Manifold ] Intake Manifold.

- Disconnect vacuum line - 1 - from brake booster of tandem pump - 5 -.





- Disconnect central connector for pump injector units - 3 -.

- Disconnect fuel hose - 2 - at tandem pump - 5 -.

- Remove bolts - arrows -.

- Remove tandem pump - 5 - from cylinder head.

- Pull tandem pump - 5 - slightly upward, remove fuel hose - 4 - and remove tandem pump.

Installing

Installation is performed in the reverse order of removal, noting the following:

• Make sure that tandem pump coupling has proper seating in camshaft.

• Tandem pump seals must always be replaced.

- Connect fuel line - 4 - with new sealing rings to tandem pump - 5 - and tighten banjo bolt to 25 Nm.





- Install tandem pump and tighten bolts - arrows -.

Tightening Specifications:

• M6: 8 Nm

• M8: 20 Nm

- Connect fuel hose - 2 - and vacuum line - 1 - to tandem pump.

- Connect central connector for pump injector units.

With engine Code BKW

- Install fuel filter. Refer to --> [ Fuel Filter ] Fuel Filter.

With Engine Code BWF

- Install bypass flap with cooler for EGR. Refer to --> [ Bypass Flap with Cooler Assembly Overview ] .

Continuation for All

- Install intake manifold. Refer to --> [ Intake Manifold ] Intake Manifold.

- Perform test drive and check Diagnostic Trouble Cove (DTC) memory. Refer to --> [ Engine Control Module, DTC Memory Checking and Erasing ] Component Tests and General Diagnostics.

• By disconnecting the central connection for the pump-injector unit, DTCs will be stored. Query the fault memory and erase, if necessary.