First of all, the EGR system cools these by recirculating exhaust gases into the combustion chambers. It contains several components including sensors, EGR valve, and PCM. It is responsible for determining or rather deciding on the most appropriate height required for lifting the EGR valve. The current flow to the EGR valve is adjusted by the PCM depending on specific conditions experienced while operating. To replace this, remove the engine cover, disconnect the electrical connector, remove the valve and old gasket. For installation, install a new valve and gasket.