•  The EGR cooler cools EGR gas and improves the intake-air charging efficiency, reducing black smoke.

•  For control of EGR system, refer to CONTROL SYSTEM, EGR CONTROL. (See EGR CONTROL OUTLINE [WL-C, WE-C].) (See EGR CONTROL BLOCK DIAGRAM [WL-C, WE-C].) (See EGR CONTROL OPERATION [WL-C, WE-C].)