ti fuel economy
 

A decent 318ti should make around 28-32 mpg.

Model: 318ti M-Sport
Year: March 1997 - built to order
Transmission: manual
Tires: 225/50ZR16
Mileage: 486,032 miles Conti Extreme Contact DWS
Odometer Reading
Fuel used: Sunoco - regular with max mileage catalyst
80 highway 20% city

My results translates into;
343.90 miles = 10.817 gallons = 31.79 mpg
(didn't use the low fuel light)