Exhaust Gas Recirculation (EGR) Control

To lower exhaust gas nitrogen oxide emissions, an exhaust gas recirculation system is incorporated within the ECCS. This is accomplished by returning a portion of exhaust gases from the exhaust manifold to the intake manifold and then to the combustion chamber to be reburned. This is controlled through the EGR valve and EGR control solenoid valve.

Under some or all of the following conditions the EGR system does not operate: engine starting, throttle valve switch on, under heavy load, low engine temperature, high engine temperature and high engine speeds. Except under the previously named conditions, when the ECU signals the EGR control solenoid, it energizes the coil within the control solenoid which pulls the plunger downward and shuts off the vacuum signal to the EGR valve.