Gas mileage decrease ? 1998 Olds 88 3.8 VIN K
The gas mileage for my 1998 Olds 88 has decreased from about 30 hwy to 23 over the past year or so . The vehicle has 71K miles ( even now gets light use). The car got a new fuel rail and FPR under recall a couple of years ago , has new plugs, air filters and oil is changed 2X year (less than 7k mile per year) . I have been told that it is very common to have a "lazy" oxygen ( O2 ) sensor ($55 ) and /or "lazy" mass air flow (MAF) sensor ( $150 rebuilt ) that will cause mileage drop but not trigger codes . Is this correct ? Any suggestions on what to do next ? - Thanks
Last edited by rkpatt; 07-31-2008 at 09:17 AM.