Coolant sensor light may be due to bad wiring. Had the same issue and my indy repaired the wiring after I cleaned it a couple times. Believe it was the connector from the wiring harness.
MPG can be due to so many things. Air leak, tuneup, poor gas, weather. Also, I just cannot see how a K&N can help anything. Just my opinion.
Last edited by Russell; 03-05-2009 at 09:21 AM.
Thanks,
1995 525i Auto, M50TU 2.5L, EAT chip, 1/95 build, USA, 205/65/15 tires, ASC+T, HID, lumbar, EC Mirror, BMW Alpine 5 radio with BMW-Pioneer CD Changer, abt 236k miles, Oxford Green/Parchment