C - Entire System Pressure Test, 3.0L TDI Vehicles

Courtesy of AUDI OF AMERICA, LLC

-- Disassemble the :VAS6551/6  and remove it with the measuring container.

• Fuel delivery rate and pressure test in the fuel supply is OK.
• The :VAS6551/7-2  connected to the fuel supply hose and the : VAS6551  .
• Vehicle Diagnostic Tester is connected.

-- Connect the :VAS6551/7-1  on the fuel supply hose to the high pressure pump and the : VAS6551  .

Courtesy of AUDI OF AMERICA, LLC

Continuation For All Vehicles 

Fig 1: Identifying Shut-Off Valves A And B On Pressure Tester Kit

Courtesy of AUDI OF AMERICA, LLC

-- Switch on the :VAS6551  -1- by pressing the On/Off  button.

-- Open the shut-off valves -A and B-.

• The lever points in the flow direction.

-- Connect the Vehicle Diagnostic Tester.

-- Switch the ignition on.

-- Select diagnostic  and start.

-- Select the button Individual tests  and select the following tree structures one after the other:

• Drivetrain 
• Select the engine code and engine 
• 0001 - OBD-capable system 
• 0001 - Engine electronics 
• 0001 - Engine electronics, functions 
• 0001 - Fuel pump activation 
• Preform the test 

-- Start the fuel pump and let it run for 15 seconds.

-- Read the fuel pressure in the :VAS6551  .

• Specified Value: 3.8 to 5.8 bar (55.11 to 84.12 psi). 

If specified value is not reached, although the fuel delivery rate was OK:

• The high pressure pump overflow valve is not OK

If specified value is exceeded:

• The fuel return line is blocked or kinked.