Test Description

The numbers below refers to the step numbers on the diagnostic procedures.

1. 2 -  This step is to run the HO2S heater tests and initiate the EVAP system test.
2. 3 -  This step is to run the EVAP, AIR and the oxygen sensor tests. The EVAP test begins once the engine coolant reaches a calibrated temperature. The AIR test, if equipped, begins shortly after Closed Loop and the indicated speed is achieved. The oxygen sensor tests begins once the engine is at operating temperature, in closed loop fuel control, and a calibrated amount of time has elapsed.
3. 4 -  This step is to run the Catalyst Tests. This test runs during the idle period immediately following a cruise period that meets a minimum calibrated RPM and time period.
4. 6 -  The I/M System Status only reports on whether or not a diagnostic has run, not what the outcome of the test was. If any emission related DTC sets after the tests are complete, the DTC will require diagnosis.