Does anyone here know any hard components under the hood that could malfunction to cause a drastic drop in gas mileage? Was averaging over 23 in town but now im getting around 12 and im really just trying to figure out how to get my mpg's back up so if anyone knows about this some help would be appreciated.

 

You could check the thermostat. If it doesn't function properly it could open too soon and the engine might not warm up enough, causing the engine to run rich for much longer than needed.

 

check your airfilter and make sure that its not completely plugged.

 

How many miles on your car? And did you install any part recently?

I can help you get your mpg back up. I have a lot of experience in that haha.

 

There is almost nothing you can do to drop you MPG by 50%. You either have some one stealing your gas or your gas gauge is bad.
There was someone else on this forum that had the same issue. Found that some one was heisting his gas.

If there was something that wrong you would be throwing CEL's.

 

Are you basing this on the actual gas you're buying, or by the average mileage read out?

May sound dumb, but recently I was stuck @ 14.1 mpg regardless of my driving, and I was a little concerned. Once I reset the gauge, my highway driving jumped to 24 mpg plus and my average was 17+. It was only a gauge error.

 

This.

 

That^

 

My gas mileage seems to go up when I use premium gas. Lot worse on regular.

 

^^or the other^^

I 'think' the winter blend gas is gone now. My mpg's are going up with this tank of gas.

 

Just for comparison sake I'm averaging 24.3 and it doesn't move now up or down because I don't reset it. If I was getting 12, I would be going to a dealer asap. I'm guessing bad sensor!!!