But should it have changed my gas mileage that much.

 

no.

Something else is the problem, I would have guessed the heavy foot as well to hear the exhaust but if you say your not doing that i don't know what else could be the issue. I would honestly make sure that all your O2 sensors are ok and that you have no exhaust leaks.

 

So even the smalles leak could make a difference. The first week after I got it my gas mileage was fine. It seemed after that first week that all went downhill.

 

bump.

 

bump

no exhaust leak.

next

 

O2 sensor

 

How hard is it to change 02 sensors. Also should they have went out already the car is barley a year old.

 

they shouldnt but it can happen, they will foul out of blue and then to the tanks goes your milage and response.

 

If my 02 sensor was bad wouldnt i get a ses light.

 

bump.

 

you most certainly should get a CEL if the sensor goes bad.