So to get your proper MPG you would divide your total miles traveled since your last fill up, by the amount of fuel it took to fill up your tank (all the way)?

 

um i have no idea, how would i check? and how do i turn it on if its off? and what is overdrive?

 

Yeah, i didnt think it might not go into overdrive, what RPM range is it in when your driving down the road at a constant rate of speed? i'd say anything over 3k its not going into overdrive. Not sure where the button is for overdrive on these cars but on my old ranger it was right on the shift ****. It might also say "overdrive off" on your instrument cluster. Overdrive basically goes to the next highest gear when your at your cruising speed so that you save on gas. Your mpg on your best tank is like 13.77 mpg, something is really wrong... take it to the dealer. If your system is running rich its killing your cats and you will not be able to pass inspection down the road if you have emmisions testing.

 

there is no button in the tC for auto drive... do you drive with the car in D or in 3? D = over drive 3 = no.

 

i drive in D all the time

 

Best bet is to just take it in, hopefully what ever is the issue is covered under warranty.

 

Overdrive is technically the highest gear, not the next highest gear. On a manual, it is 5th, since it is an overdrive gear (output speed is higher than input speed).

Sounds like you may have some poor mileage, but you still arent measuring it correctly. I dont care how many miles you put on it at 1/4 tank. Again, fill up, record mileage, drive till you want to fill it up again, fill it up and record amount of fuel it took and mileage. 90% of people complaining about the mileage (that I have seen at least) are doing as you are and not correctly measuring it, so they are actually not as bad off as they think.

 

I just got 195 miles on a bit less than 1/2 a tank(8.15 gallons). I calculated that to be 24 miles per gallon.

 

on a recent road trip done 80-85mph we got 428 miles on 12.3 gallons. (34.7mpg) that is the best tank ever. worst was like 21.5mpg(remote start and all city driving.)

but gas milage is all in the way u drive, yes heavy rims hurt gas milage alot, drop about 2-3 mpg off my other car.

and fast starts can hurt also, letting your engine hit 5 grand every shift can also hurt big time, that is what most people do when they have an intake or exhaust (trd here btw)