Evaporative Emissions System: Testing and Inspection

Evaporation system emissions, leak detection

Note! The illustrations in this service information are used for different model years and/or models. Some variation may occur. However, the essential information in the illustrations is always correct.

Smoke machine
The smoke machine generates smoke that is used to detect leaks in the EVAP- system. Follow the instructions that are supplied with the smoke machine to use it and to check for leaks.

Information
To be able to check for leaks in the whole EVAP-system, the connections must be disconnected and the smoke machine must be connected in such a way that the smoke is not stopped by non-return valves or by the EVAP-pump being closed. Two persons should help each other when checking for leaks. One that operates the smoke machine and one that visually checks for leaks.

Hint: To see the smoke easier, use a powerful light with flood lights.

The smoke contains a colouring agent that leaves invisible marks in case of leaks. These marks are seen as small green spots when they are illuminated with UV-light and yellow screened glasses are used for viewing.

Connecting smoke machine




This shows the procedure for a 5-cylinder turbo engine.
Other engine alternatives have similar EVAP-systems.
Disconnect the EVAP-pump, located under the inlet manifold in front of the engine in rubber mounting. Press together the lock on the outlet hose (1) and pull it loose. Press aside the lock on the connector (2) and disconnect it.




Clamp shut the hose closest to the connection to inlet manifold with locking pliers.




The EVAP-pump sucks in hydrocarbons through the line mounted with quick-coupling (1). The hose (2) receives vacuum since it is connected to the inlet manifold.
The non-return valve results in gas only being able to flow in to the inlet. The other hose (3) leads in to the connection before the turbo.
Disconnect the hose (4) at the EVAP-pump. Connect the smoke machine to the hose that you just disconnected. Fill the hoses with smoke and check that the hoses and non-return valves are intact.

Check for leaks in plastic hose to carbon canister




Insert the smoke machine's tapered nozzle in the line that was installed with quick-coupling in the EVAP-pump (1). Lift up the vehicle according to: Jacking points, body Service and Repair.
Fill the system with smoke. Check that there are no leaks in the hose to the carbon canister.

Note! It is natural that smoke seeps out at the tank pipe.

Finishing

Install:
- the hose on the EVAP-pump
- the hose with quick-coupling
- the connector
- the EVAP-pump with its rubber mount.

Note! Make sure that the locks on the quick-coupling and connector are locked securely.

Remove the lock grip pliers.