Air Injection System: Description

The pulse air injection system is used only on the 4.2L engine. System utilizes the alternating positive and negative exhaust pressure pulsations (instead of an air pump) to inject air into the exhaust system. This injection of air burns the unburned fuel in the exhaust system, which reduces the amount exhaust emissions escaping into the atmosphere. System consists of a Micro Computer Unit (MCU), air injection check valve, air control valve, air switch solenoid, and vacuum storage tank.