Pressure Retention Test

WARNING: This page is about a different car, the 2014 Volkswagen Touareg, 2013 Volkswagen Touareg, 2012 Volkswagen Touareg, and 2011 Volkswagen Touareg. However, it is still accessible from the selected car via links, so may be relevant.

-- Set valve -D- to "Test". Increase the current pressure until it reaches 10 in. H2O (25 mbar).

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Observe the pressure gauge -C- and flow meter -E-. If the flow quantity decreases and pressure increases to 10 in. H2O (25 mbar), then the fuel system is full.

NOTE:

Depending on the level in the fuel tank, this procedure may take up to 3 minutes.

-- After the pressure has stabilized, set valve -D- to "Hold".

After 5 minutes the pressure must not drop below 8 in. H2O (20 mbar).

If the Pressure Is Not Maintained for 5 Minutes, The Leak Should Be Localized As Follows:

-- First check the EVAP Canister Purge Regulator Valve 1 -N80- for leaks. Clamp off the hose to the EVAP Canister Purge Regulator Valve 1 - N80- with a hose clamp -arrow-.

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Repeat pressure test by resetting valve -D- to "Test".

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Observe pressure gauge and flow meter. If the flow quantity decreases and pressure increases to 10 in. H2O (25 mbar), then the fuel system is full.

-- After the pressure has stabilized, set valve -D- to "Hold".

-- If the pressure now stops decreasing, replace the EVAP Canister Purge Regulator Valve 1 -N80-.

If the pressure still decreases, perform "leak test in fuel system". Refer to FUEL SYSTEM LEAK TEST .

After completing the work, perform the "Check tank ventilation system for leaks" Guided function using Vehicle Diagnostic Tester.