Evaporative Emissions System: Testing and Inspection

EVAP CANISTER
Check EVAP canister as follows:
1. Pinch the fresh air hose.
2. Blow air into port (A) and check that air flows freely through port (B).




TIGHTENING TORQUE
Tighten EVAP canister as shown in the figure.
Make sure new O-ring is installed properly between EVAP canister and EVAP vent control valve.







FUEL TANK VACUUM RELIEF VALVE (Built into fuel filler cap)
1. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.

Pressure: 16.0 - 20.0 kPa (0.163 - 0.204 kg/sq.cm , 2.32 - 2.90 psi)

Vacuum: -6.0 to -3.5 kPa (-0.061 to -0.036 kg/sq.cm , -0.87 to -0.51 psi)

3. If out of specification, replace fuel filler cap as an assembly.

CAUTION: Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may come on.




EVAP SERVICE P0RT
Positive pressure is delivered to the evaporator system through the evaporator service port. If fuel vapor leakage in the evaporator system occurs, use a leak detector to locate the leak.







How to detect fuel vapor leakage

CAUTION:
- Never use compressed air or a high pressure pump.
- Do not start engine.
- Do not exceed 4.12 kPa (0.042 kg/sq.cm , 0.6 psi) of pressure in EVAP system.

With Consult
Attach the adapter for the EVAP service port and pressure pump to the EVAP service port. Check that the CONSULT display is in the "WORK SUPPORT" mode. Select the "EVAP SYSTEM CLOSE" item. A bar graph (pressure indicating display) will appear on the screen. To locate the leak, deliver positive pressure to the EVAP system until the pressure indicator reaches the center of the bar graph.

OR

Without Consult
Attach the adapter for EVAP service port and pressure pump with pressure gauge to the EVAP service port. Apply battery voltage between the terminals of EVAP canister vent control valve and vacuum cut valve bypass valve to close the EVAP system. To locate the leak, deliver positive pressure to the EVAP system until pressure gauge points 1.37 to 2.75 kPa (0.014 to 0.028 kg/sq.cm , 0.2 to 0.4 psi).