AIR System (Typical)

Air System (Typical):

The AIR pump (7) is controlled by the PCM. The PCM will turn ON the AIR pump by providing the ground to complete the circuit which energizes the AIR pump relay. When air to the exhaust ports is desired, the PCM will turn ON the AIR Solenoid valve and then the AIR pump.

The PCM turns ON the AIR pump during startup any time engine coolant temperature is above -10°C (14°F). The AIR pump operates for a maximum of 240 seconds, or until the system enters Closed Loop operation. At the same time the PCM turns the AIR pump OFF, it also de-energizes the AIR Solenoid Valve so no vacuum is applied to the AIR Shut Off Valve (5).

The AIR system will be disabled under the following conditions:
^ When the PCM recognizes a condition and sets a diagnostic trouble code.
^ When the fuel system is operating in Closed Loop.
^ The AIR pump has been ON for 240 seconds.
^ Engine Speed is greater than 2825 RPM.
^ MAP is greater than 96 kPa with VSS over 60 mph.
^ MAP is less than 20 kPa.
^ ECT less than -10°C (14°F).
^ 3-way catalytic converters over temperature detected.
^ Short and long term fuel trim are not in the normal range.
^ Power enrichment is detected.