EGR Operation

Exhaust gas recirculation is controlled by the ECCS. A signal is sent to the vacuum control modulator, which provides a regulated vacuum supply to open the EGR valve.

EGR operation is affected by cylinder head temperature, throttle valve position, and ignition switch position. Recirculation only takes place when the engine is operating above idle, with cylinder head temperature between 135-239°F (57-115°C).