Fuel System, Checking For Leaks

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.

Special tools and workshop equipment required

K-Jetronic Fuel System Tester:VAG1371

Work Procedure

-- Remove the right rear wheel and wheel housing liner

-- Disconnect the vent line -arrow- to solenoid valve inside the engine compartment.

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-- Connec the K-Jetronic Fuel System Tester: VAG1371 to the vent line -arrow- as shown.

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-- Connect the valve on the K-Jetronic Fuel System Tester:VAG1371 to the tire valve.

-- Remove the cover -arrow- from the vent connection on the Evaporative Emission (EVAP) canister and then seal off the opening with a plug.

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-- Set pressure to 35 mbar (0.5 psi) using valve -A-. After the pressure has stabilized, it must not drop below 30 mbar (0.4 psi) for the next 5 minutes.

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If pressure does not build up or if positive pressure is not maintained for at least 5 minutes, locate leak as follows:

-- Perform a visual inspection on all fuel system components and hoses.

NOTE:

Also check the fuel cap for leaks.

Only when up to now no malfunction has been detected:

-- Check the vent line and the EVAP canister for leaks. To do this, disconnect the vent line -1- from the EVAP canister and seal off the connection with a plug.

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-- Repeat the pressure test.

If the pressure still drops, search for the leak on the EVAP canister or the vent line:

-- With valve -A- open, check the following lines and components for leaks by listening, touching, using standard leak detection spray or using the Ultrasonic Tester:VAG1842 .

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Line from engine compartment to EVAP canister.
EVAP Canister

If pressure no longer falls now, search for leak on the fuel tank.

-- To do this, connect the vent line to the EVAP canister.

-- With valve -A- open, check the fuel tank for leaks by listening, touching, using standard leak detection spray or using the Ultrasonic Tester:VAG1842 .

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CAUTION:

After completing work, check tire pressure!