FUEL DELIVERY RATE, CHECKING, VEHICLES WITHOUT Fuel Pump Control Module -J538-

WARNING: This page is about a different variant/trim than selected.

Special tools and workshop equipment required

Trim Removal Wedge: 3409
Injection Rate Comparison Meter Kit - Remote Cable: VAG1348/3A
Multimeter, for example Analog/Digital Multimeter: FLU83III
Vehicle Diagnostic Tester - Test Adapter - 5 Pin: VAS5565
Pressure Tester Kit: VAS6550
Pressure Regulator Valve: VAS6550/4
Vehicle Diagnostic Tester
Measuring container, three liter

NOTE:

If driving is still impaired with the fuel tank a maximum of ¹ /₄ full, then perform a fuel delivery test with the fuel tank only ¹ /₄ full or with very little fuel in the fuel tank.

Test Conditions:

Voltage supply OK. Refer to FUEL PUMPS, CHECKING FUNCTION AND POWER SUPPLY, VEHICLES WITHOUT Fuel Pump Control Module -J538- .
Fuel pressure is OK. Refer to FUEL PRESSURE, CHECKING .
The battery voltage must be at least 11.5 V. Charge if necessary. Refer to BATTERY, CHARGING .
Fuel Pump Control Module -J538- fuse OK. Refer to the appropriate Wiring Diagram.
Fuel Pump Control Module -J538- is OK use the Vehicle Diagnostic Tester.
Fuel Pump Relay -J17- OK use the Vehicle Diagnostic Tester.
Fuel pump fuse OK. Refer to the appropriate Wiring Diagram.
Pull on the connector without pressing the release to make sure the connection is secure. Repeat the fuel pump function test if the connector was not connected correctly.
Fuel level inside the fuel tank is above the reserve

Test Sequence:

NOTE:

Follow the guidelines for clean working conditions. Refer to PARKING/AUXILIARY HEATER AND FUEL SYSTEM CLEAN WORKING CONDITIONS .

Pay attention to all safety precautions. Refer to SAFETY PRECAUTIONS .

Checking the Fuel Delivery Rate in the Engine Compartment:

-- Remove the rear bench seat. Refer to BENCH SEAT/SINGLE SEAT, REMOVING AND INSTALLING .

-- Unclip the cover -1- at the tabs in direction of -arrows- using the : 3409 .

Fig 1: Identifying Right Cover

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Pull on the connector -arrow- without pressing the release to make sure the connection is secure.

Fig 2: Fuel Pump Control Module Connector

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

If the connector was not connected correctly, it could cause a fault.

-- Release and disconnect the connector -arrow-.

-- Check the contacts on the connector and on the fuel delivery unit for damage.

-- Attach the : VAS5565 to the connector and to the fuel delivery unit.

Fig 3: Connecting Remote Control V.A.G 1348/3A To Test Instrument Adapter/DSO (5-Pin) VAS 5565 And To Battery Plus (+)

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the : VAG1348/3A to the : VAS5565 and the battery positive terminal clamp in the engine compartment.

NOTE:

This step allows the fuel pump to run when the engine is not running.

-- The fuel pump delivery rate is dependent on the battery voltage. Also connect the : FLU83II to the wires -1 and 5- in the : VAS5565 .

Fig 4: Connecting Multi-Meter To Wires -1 And 5- Of Adapter VAS 5565

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-- Remove the supply line -1-. Disconnect the connector couplings. Refer to CONNECTOR COUPLINGS, DISCONNECTING .

Fig 5: Disconnecting Fuel Supply Line

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CAUTION:

The fuel system is under pressure.

Risk of injury from fuel spraying out.

Wear protective eyewear.
Wear safety gloves.
Reduce the pressure: place clean cloths around the connection point and carefully open the connection point.

-- Collect leaking fuel with a cleaning cloth.

-- Connect the : VAS6550/2 to the connection -A- on the : VAS6550 .

-- Connect the : VAS6550/4 to the : VAS6550 connection -B-.

Fig 6: Connect Fuel Line From Fuel Tank Using Pressure Tester Kit VAS 6550

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the : VAS6550/2 to the fuel line from the fuel tank.

-- Hold the open end of the : VAS6550/4 hose in a measuring container.

-- Pull on the connector couplings to check them for secure fit.

-- Make sure that the drain valve -C- on the Pressure Tester -1- is closed.

Fig 7: Identifying Shut-Off Valves A And B On Pressure Tester Kit

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- The shut-off valves -A and B- on the Pressure Tester Kit -1- are opened.

-- Push the : VAG1348/3A .

NOTE:

The Transfer Fuel Pump -G6- is activated!

-- Adjust the pressure to 4.0 bar (58.01 psi) with the adjustment wheel on the Pressure Regulating Valve -arrow-.

Fig 8: Pressure Setting Knob

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- From this point on do not move the adjustment wheel.

-- Empty the measuring container.

-- Press the remote control for 60 seconds while measuring the fuel pump voltage.

-- Compare the delivered quantity of fuel with the specified value in the table.

Fig 9: Identifying Graph Of Voltage Versus Delivery Rate

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Example:

During test, a voltage of 10.5 Volts is measured. This results in a minimum delivery quantity of approximately 1200 cm³ /60 s.

If Specified Value Is Not Reached:

Fig 10: Filler Cap

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-- Open the fuel filler door unit.

-- Clean the area around the fuel filler neck.

-- Remove the cap -arrow- for the fuel filler tube.

-- Check the fuel delivery rate again. Refer to FUEL TANK, CHECKING VENTILATION .

If Specified Value Is Reached:

-- Check the fuel tank ventilation.

If Specified Value Is Not Reached:

-- Check the fuel lines for possible restrictions (kinks) or blockages.

-- Check the fuel lines for leaks and damage.

If No Error Can Be Found:

Proceed as follows to check the fuel delivery rate to the fuel filter.

Checking the Fuel Delivery Rate to the Fuel Filter:

Fig 11: Fuel Supply Line At Fuel Filter

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Disconnect the fuel supply line -arrow- from the fuel filter. Disconnect the connector couplings. Refer to CONNECTOR COUPLINGS, DISCONNECTING .

CAUTION:

The fuel system is under pressure.

Risk of injury from fuel spraying out.

Wear protective eyewear.
Wear safety gloves.
Reduce the pressure: place clean cloths around the connection point and carefully open the connection point.

-- Connect the : VAS6550/1 to the connection -A- on the : VAS6550 .

-- Connect the : VAS6550/4 to the connection -B- on the : VAS6550 .

Fig 12: Connecting Pressure Tester Kit - Hose 1 VAS 6550/1

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-- Connect the : VAS6550 to the fuel supply line -2- with the : VAS6550/1 .

-- Hold the open end of the : VAS6550/4 hose in a measuring container.

-- Make sure that the drain valve -C- on the Pressure Tester -1- is closed.

Fig 13: Identifying Shut-Off Valves A And B On Pressure Tester Kit

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- The shut-off valves -A and B- on the Pressure Tester Kit -1- are opened.

-- Push the : VAG1348/3A .

NOTE:

The Transfer Fuel Pump -G6- is activated!

-- Adjust the pressure to 4.0 bar (58.01 psi) with the adjustment wheel on the Pressure Regulating Valve -arrow-.

Fig 14: Pressure Setting Knob

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- From this point on do not move the adjustment wheel.

-- Empty the measuring container.

-- Press the remote control for 60 seconds while measuring the fuel pump voltage.

If Specified Value Is Reached:

-- Check the fuel line to the engine for possible kinks or blockages.

-- Check the fuel line to the engine for leaks and damage.

If No Malfunction Was Detected:

-- Replace the fuel filter. Refer to FUEL FILTER, REMOVING AND INSTALLING .

If Specified Value Is Not Reached:

Check the fuel delivery rate on the fuel delivery unit as follows:

Fuel Delivery Rate, Checking on Fuel Delivery Unit:

Fig 15: Fuel Lines At Flange

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-- Pull the fuel line -1- off the flange. Disconnect the connector couplings. Refer to CONNECTOR COUPLINGS, DISCONNECTING .

CAUTION:

The fuel system is under pressure.

Risk of injury from fuel spraying out.

Wear protective eyewear.
Wear safety gloves.
Reduce the pressure: place clean cloths around the connection point and carefully open the connection point.

-- Connect the : VAS6550/2 to the connection -A- on the : VAS6550 .

-- Connect the : VAS6550/4 to the connection -B- on the : VAS6550 .

Fig 16: Connect Pressure Tester Kit - Hose 1 VAS 6550/1

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the : VAS6550 to the fuel delivery unit -1- with the : VAS6550/2 .

-- Hold the open end of the : VAS6550/4 hose in a measuring container.

-- Make sure that the drain valve -C- on the Pressure Tester -1- is closed.

Fig 17: Identifying Shut-Off Valves A And B On Pressure Tester Kit

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- The shut-off valves -A and B- on the Pressure Tester Kit -1- are opened.

-- Push the : VAG1348/3A .

NOTE:

The Transfer Fuel Pump -G6- is activated!

-- Adjust the pressure to 4.0 bar (58.01 psi) with the adjustment wheel on the Pressure Regulating Valve -arrow-.

Fig 18: Pressure Setting Knob

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- From this point on do not move the adjustment wheel.

-- Empty the measuring container.

-- Press the remote control for 60 seconds while measuring the fuel pump voltage.

If Specified Value Is Not Reached:

Fig 19: Identifying Delivery Unit Fuel Hoses

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Remove the fuel delivery unit. Refer to FUEL DELIVERY UNIT/FUEL LEVEL SENSOR, REMOVING AND INSTALLING .

-- Check the fuel lines for possible restrictions (kinks) or blockages.

-- Remove the fuel delivery unit and check the filter screen for contamination.

-- Check the fuel lines for leaks and damage.

-- Check whether the hose connections -arrows- to the fuel delivery unit -1- are sealed.

If No Malfunction Was Detected:

-- Check the current draw of the fuel pump. Refer to CURRENT DRAW, CHECKING .

If No Faults Were Found While Checking the Current Draw:

-- Replace the fuel delivery unit. Refer to FUEL DELIVERY UNIT/FUEL LEVEL SENSOR, REMOVING AND INSTALLING .

If the fuel delivery rate was reach, even though a fault in the fuel supply is still suspected (for example, intermittent loss of fuel supply):

-- Check the current draw of the fuel pump. Refer to CURRENT DRAW, CHECKING .

Tightening Specifications

Refer to OVERVIEW - FUEL DELIVERY UNIT/FUEL LEVEL SENSOR