Corsica V6-3100 3.1L MFI VIN M (1994)
EGR Valve: Description and Operation
EGR Valve (Digital)
Digital EGR Valve Circuit Diagram
PURPOSE
The exhaust gas recirculation (EGR) system is used to reduce oxides of nitrogen (NOx) emissions. The atmosphere is made up of mostly Nitrogen,
with a smaller percentage of oxygen, and a mixture of other gases. Oxygen and Nitrogen do not normally combine except at very high
temperatures and pressures, conditions which are present in the combustion chamber especially during hard acceleration. When the engine is under
load, the EGR valve admits a small amount of exhaust gas into the intake manifold to mix with the air/fuel charge. The exhaust gas is essentially
inert (contains no fuel or oxidizer) and reduces peak combustion temperatures and pressures by absorbing some of the heat of combustion without
participating in the actual burn. Greater amounts of exhaust gas are metered in as engine speed and load are increased.
The digitally controlled EGR valve is designed to accurately supply regulated amounts of exhaust gas to the intake manifold, independent of
manifold vacuum.
OPERATION
EGR solenoid valves get battery power when the ignition is turned "ON" and become energized when the control module completes the circuit to