EGR System: Operation: Notes

On non-turbocharged engines, amount of exhaust gas recirculation is controlled by ported vacuum and exhaust gas pressure. The EGR valve should be closed when any one of the following conditions is met: sudden acceleration, sudden deceleration, closed throttle deceleration, idle, radiator coolant below 63°F (17°C), engine coolant below 158°F (70°C) or engine speed below 1500 RPM.

On turbocharged engines, amount of exhaust gas recirculation is controlled by engine conditions. The EGR valve will be half closed during sudden acceleration. The EGR valve will be fully closed when any one of the following conditions is met: throttle plate is closed, sudden deceleration, radiator coolant below 63°F (17°C) or engine coolant below 104°F (40°C).