Component Tests and General Diagnostics

Y. CHECKING THE EVAPORATIVE EMISSION (EVAP) SYSTEM

Y1

Checking The Evaporative Emission (EVAP) Valve

-Disconnect the ventilation hose and the canister control from the TB.




-Connect a vacuum pump to the ventilation hose (the thick hose) and pump out air.

When pumping a partial vacuum should be displayed on the meter.

The pressure quickly returns to atmospheric pressure. However there is a noticeable resistance to pumping.

If partial vacuum and resistance are OK:

-Check vacuum hose

If partial vacuum or resistance are not obtained:

-Check the ventilation hose to the canister for damage or leaks.

If the ventilation hose is OK:

-Try using a new canister.

Y2

Checking The Vacuum Hose




-Pump air out of the vacuum hose (the thin hose). The meter should display a partial vacuum.

If a partial vacuum is obtained:

-Check the canister control Y3

If no partial vacuum is obtained:

-Check the vacuum hose for damage or leaks.

If the vacuum hose is OK:

-Try using a new canister

Y3

Checking The Canister Control

-Release the vacuum.

-Blow into the ventilation hose (the thick hose).

The hose should be airtight.

If the ventilation hose is not airtight:

-Check the hose for damage.

If the hose is OK:




-Pump air out of the thin hose.

-Blow into the ventilation hose again.

It should be possible to blow through the canister valve with only a light resistance.

If the valve is OK:

The canister and canister control are OK.

-Return to fault tracing where it was interrupted.

If the valve is sealed.

-Try using a new canister.