I just bought a 97 STS. My wife drove a 2000 STS. When I say drove I mean drove it into a flood and totaled the car. We replaced it with a 2004 Deville. She loves it. I bought a 97 STS for myself. It fantastic. I was wondering if there is anything non mechanical to improve the mileage. It gets about 16 MPG. The car has 148000 miles. Do gas additives or a K&N filter really do anything?

 

double posting ....