Fuel Pump Check Valve

WARNING: This page is about a different car, the 2008 Volkswagen R32. However, it is still accessible from the selected car via links, so may be relevant.

-- Open the cover of the relay and fuse panel in the engine compartment E-box.

-- Remove fuse SB6 in position F6 on fuse holder.

-- Connect the VAG 1348/3A with the VAG 1348/3-3 to the left terminal (in direction of vehicle travel) of fuse socket F6 -arrow-.

Fig 1: Identifying Hand Held Remote Control (Jumper) Connected To Left Terminal Of Fuse Socket F6

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Using insulating tape, tape over the second contact of the VAG 1348/3-3 to prevent a short circuit.

-- Connect the alligator clip to the vehicle's battery positive terminal.

WARNING:

Fuel system is under pressure! Wear protective goggles and protective clothing to prevent injuries and contact with skin. Before disconnecting the connection, wrap a cloth around the connection. Then release the pressure by carefully disconnecting the connection.

-- Remove the fuel supply line -1- from the inlet to the fuel filter.

Fig 2: Identifying Pressure Tool To Check Fuel Pump Non-Return Valve

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

NOTE:

Press in the securing ring to disengage the fuel line.

-- Install the VAG 1318 with the VAG 1318/17A as shown.

-- Connect the VAG 1318/1 to the VAG 1318/11 installed on the VAG 1318 and hold the other end of the VAG 1318/1 in a measuring container.

-- Close the shut off lever on the VAG 1318 (lever at right angle to direction of flow position -B-).

-- Operate the VAG 1348/3A at short intervals, until a pressure of approximately 4 bar has built up.

WARNING:

Danger of spraying when opening the shut off lever. Wear protective goggles and protective clothing to prevent injuries and contact with skin. Hold the container in front of the free end of the VAG 1318.

-- If pressure builds up too high, lower excess pressure by carefully opening the shut off lever.

-- Watch pressure drop on gauge.

After 10 minutes the pressure must not drop below a 3 bar decrease.

If the pressure drops further:

-- Check the line connections for leaks.

If no fault is detected in the wiring:

-- Fuel pump faulty, replace the fuel delivery unit. Refer to FUEL DELIVERY UNIT .