poor fuel economy
 

I have a 97 cirrus lxi v-6. Had 2 codes, both delt with evap system and said 1 leak was small 1 leak was big. Since then the fuel seems to drain out of the tank faster after the halfway point then it does at full or 3/4. resulting in about 200 miles per tank. When I originally bought the car I drove over 100 miles on the last 1/4 tank. There is no visible leaking of gas nor do I smell gas. Can someone help?

Update: At the halfway point of the fuel gauge I had 125 miles, by the time I got to empty I had a total of 180 miles to a tankfull out of a 16 gallon tank. The car runs great (165,000). Can anyone point me in the right direction?

RE: poor fuel economy
 

don't use use fuel gage as a guide. track the mianlge & gallons used for any sort of accuracy. checnk to see if you have the optional LARGEr fuel tank, if so i THINK they use the same fuel sending unit, THus if you have hte larger tank thye it would appear the top 1/2 of the fuel lasts long and that is due to the shape of the tank and the float rather than fuel usage( miles per gallon) If you are traveling it's about the best time to check it ,,,fill one and check to 1/2 tank & check milage,,,try and use the same speed of fill and or shut off anfd tank top off every time....
Then try it again this time until empty. if they are very close i would thin your issue may be perception rather than a problem with vechle...
the fuel system doen't really caretoo much if it has 1/4 to full tank. It's a fuel pump and pressure regulator sytem.