2008 chevy malibu gas dropping?

[john doe]

I purchased a 2008 Malibu v6 3.5liter with 47000 miles on it. when i first got it, i got about 320 miles to a tank of gas. yesterday i filled it up and it said i had 240 till empty. what can i do to make it go back? i dont drive fast or crazy, but its driving me insane because of gas prices. its supposed to get 22 in the city and 35 on the highway, help

 

[Freedom Wins IV]

You do have a regular gas gauge in that vehicle so watch it. You can also reset the trip meter on the odometer and check it the old fashion way by calculating your gas mileage over two or three full takes. There could be a problem with the sending unit which sends a signal to the onboard computer system for the telltale info system. Too many things come into play to say you aren't getting the mileage you should be getting!