Fuel Delivery, Checking

Test Conditions 

• The battery voltage must be at least 12 volts.
• The fuses must be OK.
• All electrical consumers such as, for example, lights and rear window defogger, must be turned off.

Test Sequence 

-- Disconnect the connector -1- from the auxiliary fuel pump -V393-.

Fig 1: Identifying Connector -1- To Auxiliary Fuel Pump And Fuel Hoses -2 / 3-

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Disconnect the black fuel supply line -A- from the fuel tank.

Fig 2: Identifying Fuel Supply Line -A- (Black) And Fuel Return Line -B- (Blue Or With Blue Mark)

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the pressure tester VAS 6550 to the fuel supply line -A- on the fuel tank.

-- Guide the open end of the hose from the pressure tester VAS 6550 into a measuring container.

-- Open the shut off levers in the direction of flow before and after the manometer and close the lower shut off lever.

-- Connect the vehicle diagnostic tester -1- as follows:

Fig 3: Identifying Evaporative Emissions Tester Connected To Vehicle

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the diagnostic cable -2- to the Data Link Connector (DLC) in the driver's foot well.

-- Turn on the ignition.

-- Perform the guided function "Check Electric Fuel Pumps".

-- By carefully closing the shut off lever behind the manometer, adjust the pressure to 0.5 bar.

-- Stop the vehicle diagnostic tester test sequence if necessary and empty the measuring container.

-- Guide the open end of the hose from the pressure tester VAS 6550 back into the measuring container.

-- Start the guided function "Check Electric Fuel Pumps" again.

-- Turn off the ignition.

-- Read the quantity of fuel in the measuring container.

Specified Values 

• Minimum 1950 ml/60 seconds
• Maximum 2750 ml/60 seconds

If the quantity of fuel delivered is less than the specified value:

-- Check the fuel pump voltage supply and the current draw, refer to VOLTAGE SUPPLY, CHECKING  and CURRENT DRAW, CHECKING .