Exhaust Gas Recirculation: Description and Operation

To assist in the control of oxides of nitrogen (NOx) in engine exhaust, all engines are equipped with an exhaust gas recirculation system. The use of exhaust gas to dilute incoming air/fuel mixtures lowers peak flame temperatures during combustion, thus limiting the formation of NOx.
Exhaust gases are taken from opening in the exhaust manifold passage to the intake manifold.