Thread: MPG gone down the crapper

Some how in the past three weeks or so my MPG has gone down the toilet.I used to get 275 to 280 miles out of a full tank.Now I'm lucky to get 220 miles out of a tank of gas.
The car still performs the same runs fine doesn't smell like it's running rich.I recently did a tune up with in the past three months.I have actually been granny driving to see if I could get some of my fuel mileage back.Anybody got any ideas?

any engine codes?

nope car is running fine other than the loss of the gas mileage.

fuel filter replaced?

^^about six months ago.the only thing i could think is it's the winter blend that gas stations use in the winter months.but i can't see it making me lose that much.

vacuum leaks, bad or failing CTS, bad or failing o2 sensor, set idle and timing

o2 was what i was thinking but since you dont have any codes.....how is your idle?

Idle is steady at 900rpm,replaced o2 back in june checked for vacuum leaks could not find any.haven't thought about the coolant temp sensor but my fans turn on when they are supposed to at 212 and the temp is 175 to 180ish.

how about your pcv valve? you should pull it off and shake it if it rattles its good if it doesnt rattle than its either stuck open or stuck closed, if they are stuck open it can allow a unmetered ammount of air in. and can cause bad gas mileage

has your foot become heavier in the winter boredom?