Ok, so lately (like the past 5 days or so) my gas gauge has been going down like none other. The DIC is still saying I'm getting around 30mpg, so I don't know what's going on.

I drove about 10 miles today, and it used almost 1/8 of a tank! Not cool.
The other day I drove about 25 miles, and it used almost 1/4 tank.
Yesterday I drove about 120 miles, and it used a half tank (I figured it should only take about 4 gallons, which isn't a half tank...) I had just filled up before we left.

Help! What could be going on?? I know it's been cold (Like around 10 for a high...) but could that affect it so much?

 

dam, i drove 100 miles yesterday and only used a lil more than 1/4 tank

 

^^ Which is normal!!

grrrrr

 

yea, did you race at all, or push the car a lil, i noticed itll eat quite a bit if u push the car

 

Nope. Most of it was a top speed of 55... Today I was just around town, never more than 40.

 

do you happen to be driving on the bottom half of the tank?

it was really pronounced with the sunfire/cav, but theres still a bit of it with the cobalt.
the first half of your tank tends to last longer than the second half.

 

thats also true

 

Nope. Since it's so cold I rarely let it get below half. Like I said, I filled up yesterday before leaving, so it was full. Still used almost a half tank.

 

im not sure, but compared to my honda, my cobalt gets great gas mileage

 

well cold weather does tend to hurt your mileage.

has it been noticably colder during the time youve lost mileage?

 

Have you ran your defroster?

It uses the A/C

 

Heh... yep. I bet that's it. Well I feel dumb now.

 

gas tank, fuel lines leaking?