Fuel Pressure, Checking Engine Codes CVCA

WARNING: This page is about a different car, the 2015 Volkswagen Beetle, 2014 Volkswagen Beetle, and 2013 Volkswagen Beetle. However, it is still accessible from the selected car via links, so may be relevant.

Special tools and workshop equipment required

Diesel Pressure Tester KitVAS6551
Diesel Pressure Tester Kit - Adapter Set VAS6551/5
Hose Clip Pliers VAG1921
Trim Removal Wedge3409
Vehicle Diagnostic Tester

WARNING:

Remember, the fuel pump will turn on when a door is opened, if the battery is connected. Fuel may leak out when the system is open.

Test Conditions:

Connect the battery charger. The voltage must be minimum 12.5 V. Refer to BATTERY, CHARGING .
Fuses OK; refer to the appropriate Wiring Diagram.
Fuel Pump Control Module -J538- is OK, refer to Vehicle Diagnostic Tester.
The fuel filter is OK.
Make sure the vehicle is level.
Fuel tank minimum ¹ /₂ full.
All electrical consumers such as, for example, headlamps and rear window defogger, must be off.

NOTE:

The vehicle must be fueled with diesel fuel treated for the season. Under some conditions, summer diesel fuel can coagulate at low winter temperatures.

Diesel fuel bought in the summer can be filtered to 0 °C (32 °F).

Diesel fuel sold during the transition time can be filtered to -10 °C (14 °F).

Diesel fuel bought in the winter can be filtered to -20 °C (-4 °F).

Test a sample in the winter if there is doubt.

The sample should set outside at low outside air temperature for approximately 1 hour.

If the fuel coagulates at temperatures down to -20 °C (-4 °F), then this diesel fuel is not suited for low temperatures. This coagulation can plug the screen in the fuel delivery unit as well as in the fuel filter.

Test Sequence

-- Follow all safety precautions. Refer to SAFETY PRECAUTIONS .

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

-- Turn off the ignition.

-- Remove the engine cover. Refer to ENGINE COVER .

-- Open the clamp -arrow-.

Fig 1: Identifying Clamp

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

WARNING:

Fuel lines are under pressure.

Danger of personal injury to eyes and skin.

Wear protective eyewear and protective clothing in order to avoid injury and contact with the skin. Wrap a cloth around the connection before loosening hose connections. Open the connection carefully and release the pressure.

-- Remove the fuel supply line -1- from the high pressure pump -2-.

-- Insert the Diesel Pressure Tester Kit - Adapter Set - Adapter 1VAS6551/5-1 into the supply line -1- and secure with a clamp.

Fig 2: Identifying Diesel Pressure Tester Kit - Adapter Set - Adapter 1

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the Diesel Pressure Tester Kit - Hose 2VAS6551/2 between the Diesel Pressure Tester Kit - Adapter Set - Adapter 1VAS6551/5-1 and the connection -A- of the Diesel Pressure Tester KitVAS6551.

-- Connect the Diesel Pressure Tester Kit - Adapter Set - Connection Hose 2VAS6551/5-2 between the connection -B- of the Diesel Pressure Tester KitVAS6551 and the high pressure pump -2-.

-- Secure the Diesel Pressure Tester Kit - Adapter Set - Connection Hose 2VAS6551/5-2 on the high pressure pump -2- with a clamp.

-- Press the On/Off button to switch on the Diesel Pressure Tester KitVAS6551.

-- Make sure that the drain valve -C- on the Diesel Pressure Tester KitVAS6551 -1- is closed.

Fig 3: 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- are opened on the Diesel Pressure Tester KitVAS6551 -1-.

-- Connect the Vehicle Diagnostic Tester.

-- Select Guided Function 01 activate fuel pump .

-- Select check fuel pump delivery pressure/delivery .

-- Follow the instructions given by the Vehicle Diagnostic Tester.

NOTE:

The fuel pump is activated.

-- Read the fuel pressure in the Diesel Pressure Tester KitVAS6551:

The target value is minimum 4.5 bar:

If the specification is not obtained:

-- Check the fuel lines inside the engine compartment for possible bends, blockages and damage.

-- Check the fuel lines inside the engine compartment for leaks.

If no faults are detected:

Check the fuel pressure in front of the fuel filter as follows.

Check the fuel pressure in front of the fuel filter:

-- Remove the supply line -B- and wipe up the draining fuel with a cleaning cloth. Disconnect the connector couplings. Refer to CONNECTOR COUPLINGS, SEPARATING .

Fig 4: Identifying Fuel Line Couplers

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

WARNING:

Fuel lines are under pressure.

Danger of personal injury to eyes and skin.

-- Connect the Diesel Pressure Tester Kit - Hose 2VAS6551/2 between the fuel supply line from the fuel tank and the connection -B- on the Diesel Pressure Tester KitVAS6551.

Fig 5: Identifying Diesel Pressure Tester Kit - Hose 2

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the Diesel Pressure Tester Kit - Hose 1VAS6551/1 between the connection -A- on the Diesel Pressure Tester KitVAS6551 and the fuel line -1- to the fuel filter.

-- Press the On/Off button to switch on the Diesel Pressure Tester KitVAS6551.

-- Make sure that the drain valve -C- on the Diesel Pressure Tester KitVAS6551 -1- is closed.

Fig 6: 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- are opened on the Diesel Pressure Tester KitVAS6551 -1-.

-- Repeat check fuel pump delivery pressure/delivery , refer to FUEL PRESSURE, CHECKING ENGINE CODES CVCA .

If the specification is now obtained:

Check and fuel filter and replace it, if necessary. Refer to FUEL FILTER, REMOVING AND INSTALLING .

If the specification is not obtained:

Proceed as follows to check the fuel pressure at the fuel delivery unit.

Check the fuel pressure on the fuel delivery unit:

-- Remove the rear bench seat. Refer to REAR SEATS .

-- Unclip the cover -1- at the tabs -arrows- using the Trim Removal Wedge 3409.

Fig 7: Identifying Right Cover

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

WARNING:

Remember, the fuel pump will turn on when a door is opened, if the battery is connected. Fuel may leak out when the system is open.

-- Remove the fuel return line -1- from the locking flange. Disconnect the connector couplings. Refer to CONNECTOR COUPLINGS, SEPARATING .

Fig 8: Identifying Position Of Fuel Delivery Unit Flange

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

WARNING:

Fuel lines are under pressure.

Danger of personal injury to eyes and skin.

-- Connect the Diesel Pressure Tester Kit - Hose 1VAS6551/1 between the Diesel Pressure Tester KitVAS6551 and the fuel supply line to the fuel filter.

-- Connect the Diesel Pressure Tester Kit - Hose 2VAS6551/2 between the Diesel Pressure Tester KitVAS6551 and the fuel delivery unit.

-- Make sure that the drain valve -C- on the Diesel Pressure Tester KitVAS6551 -1- is closed.

Fig 9: 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- are opened on the Diesel Pressure Tester KitVAS6551 -1-.

-- Repeat check fuel pump delivery pressure/delivery , refer to FUEL PRESSURE, CHECKING ENGINE CODES CVCA .

If specified value is achieved:

-- Check the fuel lines to the engine compartment for possible bends, blockages and damage.

-- Check fuel lines for leaks.

If the specification is not obtained:

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

-- Check the filter screen for dirt.

-- Check to make sure that all wires are connected properly.

-- Pull on the connections to make sure they are secure.

-- Make sure all the hoses are connected -arrows-.

Fig 10: Identifying Delivery Unit Fuel Hoses

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

If no fault was detected:

NOTE:

If the filter screen is not blocked or dirty, all lines are connected and the fuel pressure specified value is not reached, then the fuel delivery unit is faulty.

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