Have a 2001 Taurus SEL w/146,000 miles. Great car but had an EGR code pop up. Took it to Auto Zone and had the guy there read the code with 5 possible reasons; 4 of the 5 were EGR valve related, so replaced it with a new one. There was no change in the performance of the car, ran fine before the EGR code came up, but thought perhaps the mpg might improve with a new EGR valve, the complete opposite happened; the gas milage is incredibly worse. What up???!! Anyone have any ideas or suggestions? Thanks in advance.