Location of egr valve on 2000 mountaineer
Im going to guess v8 being all wheel drive,here a pic of the EGR.
The EGR controls fuel emmision,and vacume to your throttle body.
The EGR valve is "exhaust gas re-circulation". This valve, for pollution control purposes, sends some exhaust gasses back into the engine to clean up the combustion process. Do some reading at the link....https://en.wikipedia.org/wiki/Exhaust_gas_recirculation
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