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Description & Operation

The Exhaust Gas Recirculation (EGR) system is used to help control formation of NOx emissions. The EGR introduces exhaust gases back into intake system. The exhaust gases lower peak combustion temperatures, which lowers NOx emissions down. All EGR valves receive operating vacuum from a ported vacuum signal.

Fig 1: EGR System (SPFI Engines)
G93983Courtesy of SUBARU OF AMERICA, INC.
Fig 2: EGR System (Federal Turbo Engines)
G67256Courtesy of SUBARU OF AMERICA, INC.
Fig 3: EGR System (1.8L Carbureted Engines)
G67257Courtesy of SUBARU OF AMERICA, INC.