Air Injection System: Operation

The air injection control systems determine when fresh air is added to the exhaust ports. The switching points will vary with each engine, but the following conditions apply to all systems. Air is not injected when the engine is cold, when coolant temperature is above 230° F (110° C), or during deceleration. Air is injected under most driving conditions. On vehicles with a catalytic converter temperature probe, air injection is switched off by the computer when converter temperature is over 1445° F (785° C).