Check ventilation lines for leaks

Check the tank system for leaks using an HC tester. To do so, hold the connecting hose of the HC tester in the spot to be tested. In the case of a leak, the display of the HC tester increases to above 1000 ppm. Values below 50 ppm indicate no leaks.

To test the ventilation lines, guide the connecting hose slowly along them.

Check the following locations: 

1. Tank cap
2. Line connections to EVAP canister
3. EVAP canister
4. Line connection to fuel tank sender unit
   Fig 1: Locating Line Connection To Fuel Tank Sender Unit

   Courtesy of PORSCHE OF NORTH AMERICA, INC.
5. Pressure sensor
6. Opening of fuel filler neck into tank
7. Line connection of EVAP canister purge valve
   Fig 2: Locating Line Connection Of EVAP Canister Purge Valve

   Courtesy of PORSCHE OF NORTH AMERICA, INC.
8. Ventilation lines:
   1. from EVAP canister to operating purge valve
   2. from operating purge valve to tank
   3. from EVAP canister to EVAP canister purge valve

      If no leaks are found, a gauge pressure of max. 100 mbar (0.1 bar) can be generated at the EVAP canister at the connection to the tank using special tool 9160/1, in order to increase the escape of fuel vapours.