it is on the pass side of the motor near the firewall and it recirculates spent exhaust gases back into the intake stream in an attempt to make some of the nasty stuff get reburned for better tailpipe emissions
That's actually not why it's there. It is there to lower combustion temps to reduce NOX emissions. Exhaust gas is inert and does not burn. A nonburnable gas in the cylinder means slightly less air and fuel to burn which creates less heat during the burn. The amount which flows through the EGR is minimal and reburning what is still burnable in the exhaust gas is not worth the trouble of doing so.
