Air Injection System: Notes

Air injection system is designed to send air to exhaust manifold to reduce exhaust emissions (CO, HC and NOx). System may utilize a belt driven pump, or pulse injection type system.

Exhaust Gas Recirculation (EGR) Control (2.5L & 4.0L Engines)

To lower oxides of nitrogen (NOx) exhaust gas emissions, a computer controlled exhaust gas recirculation system is used. Coolant temperature and other inputs are monitored by ECU to determine EGR flow. ECU regulates vacuum to EGR valve through the EGR valve vacuum solenoid. Some models utilize a combined EGR/evaporative canister purge solenoid.