Evaporative Emission (EVAP) Canister System, Checking For Proper Seal

Evaporative Emission (EVAP) canister system, checking for proper seal

Special tools, testers and auxiliary items required
- Smoke tester.
- EVAP and Fuel Supply System Vacuum hose and line routing diagram.

Note:
- Secure all hose connections using hose clamps appropriate for the model type Parts catalog.
- 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. Diagnostic Mode 04: Reset/Delete Diagnostic Data

- Perform a road test to verify repair.

If a DTC was set and does not return:

Repair complete, Generate readiness code. Audi Drive Cycle/Readiness Code

- 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.

End of procedure.