I have three codes (P0131, P0171, P1153). Poor gas mileage. Any suggestions?

Question

I am getting about 60-70% of the gas mileage I should be getting. The car runs great.

Answer 1

p1153 and P0131 is for oxygen sensor (air/fuel ratio sensor) bank 1 sensor 1 and all the codes are related

if there are no exhaust leaks or damages to the exhaust, replace bank 1 sensor 1 oxygen sensor  (air/fuel ratio sensor)

is your car turbo'ed model or regular? I cant post a picture if I dont know