Test Sequence

WARNING: This page is about a different car, the 2016 Volkswagen Beetle, 2015 Volkswagen Beetle, 2014 Volkswagen Beetle, 2013 Volkswagen Beetle, and 2012 Volkswagen Beetle. However, it is still accessible from the selected car via links, so may be relevant.

-- Activate the fuel pump with output diagnostic test mode to build fuel pressure.

NOTE:

The fuel pump now activates to build up the fuel pressure.

If the output diagnostic test mode is performed several times after another it is necessary to briefly start the motor before repeating the output diagnostic test mode.

-- Read the fuel pressure on the pressure gauge.

Specified Value: ≥ 4 bar (58 psi)

-- End the On Board Diagnostics (OBD) and turn off the ignition.

Observe the pressure drop on the pressure gauge. After 10 minutes the pressure must not drop more than approximately 1.0 bar (14.5 psi)

If the pressure drops

-- Check all the fuel lines for leaks and damage.

If No Faults Can Be Found

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

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Make sure that the drain valve -C- on the Pressure Tester (Diesel) -1- is shut.

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

-- Activate the fuel pump with output diagnostic test mode to build fuel pressure.

-- Close the shut-off valve -B- on the pressure gauge immediately after the pressure has been reached. The lever is perpendicular to the direction of flow.

If the Pressure Drops Again (Leak on fuel tank side):

Proceed as follows to check the fuel filter residual pressure. Refer to Checking the Residual Pressure at the Fuel Filter .

If the Pressure No Longer Decreases (leak on the engine side):

NOTE: Look for leaks on the engine-side. Repeat the residual pressure check. Close the shut-off valve -A- this time to determine if there actually is a leak on the engine side.

-- If there is a leak on the engine side, check the fuel pipe and high pressure pump for leaks.

If No Malfunction Is Found Check the Fuel Injectors for Leaks.

-- Remove the spark plugs. Open the drains -A and B-. Activate the fuel pump with output diagnostic test mode.

-- Check through the spark plug holes if there is a leaking injector, fuel collecting on the piston head.