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), during deceleration, or when catalytic converter temperature is above 1445°F (785°C). On vehicles with oxygen sensor, air injection is switched off if air-fuel ratio is too lean.