Alright, I have a 94 Altima that has been in my family forever, and so now I am stuck with doing all the work into fixing it up. A couple years ago when my sister had it, it was solid at 26-28 mpg, but now its running as low as 18 mpg going down the highway.

I have ran a compression test and it came out green, I have checked my Knock Sensor and its fine, can't be the O2 sensor because I just passed an emission test with flying colors not a month ago, engine coolant temp is fine, new distributor with what i hope to be perfect timing, runs great and sounds great, and its not spittin any kind of smoke that is irregular. I have checked my onboard diagnostic's and it comes out 55, all clear.

If anyone has ANY idea as to why it would run so bad, please give me all of the advice you have! ha.

Thanks a million.