EVAP System, Checking For Leaks

WARNING: This page is about a different car, the 2007 Audi A3 and 2006 Audi A3. However, it is still accessible from the selected car via links, so may be relevant.

Special tools and workshop equipment required

Smoke tester.
EVAP and Fuel Supply System Vacuum hose and line routing diagram.

NOTE:

Replace seals and gaskets when performing repair work.

Leak checking

-- Using a Smoke tester, check the Evaporative Emission (EVAP) canister system for leaks.

NOTE:

Always follow the manufacturers directions for the proper installation and operation of the Smoke tester being used.

If a leak is detected:

-- Check the fuel filler cap seal for damage and for proper installation. Replace if necessary.

-- Check the seals under the locking flanges and the union nuts are properly tightened on the fuel tank.

-- Check all hose connections of the fuel supply system and replace or repair any leaking lines.

-- Check all hose connections of the EVAP system and replace or repair any leaking lines.

-- Repair or replace any damaged component.

If no leaks are found in the EVAP and Fuel Supply System:

-- Erase the DTC memory if a DTC was set. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .

-- Perform a road test to verify repair.

If a DTC was set and does not return:

Repair complete, Generate readiness code. Refer to READINESS CODE DESCRIPTION .

-- End diagnosis.

If the DTC does return and no leaks are found in the EVAP and Fuel Supply System:

-- Check the DTC memory for any DTC codes pertaining to the EVAP and Fuel Supply Systems. If a DTC is stored, perform the diagnostic test procedure for the suspected component. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .

End diagnosis.