2.8L Diesel
The Exhaust Gas Recirculation (EGR) system includes the pneumatic EGR valve, the Electronic Vacuum Modulator (EVM), and the Electronic Control Unit (ECU).
The ECU commands the EVM to open the EGR valve. The EVM routes vacuum from the vacuum pump to the pneumatic EGR valve, which lifts on the internal diaphragm in the EGR valve. The diaphragm lifts a pintle in the EGR valve which allows the exhaust gas to be recirculated into the engine.
The EGR system controls NOx emissions by reducing cylinder temperatures.