In my grandma's '92 Lincoln Continental Method used: Read stats from the "Message Center" (the equivalent of the multi-display, but in the spedo' box behind the steering wheel) Max instantaneous MPG for the day 100 MPG for 2 sec. Max instantaneous MPG sustained 70 MPG downhill for ~25-35 sec. Min instantaneous MPG 1 MPG (it is a traditional drive automatic) other details: I had the windows down most of the day, mixed farm road (50-75mph) and city driving Valet parking in the rain after lunch time 1 hour of the day's driving was in the rain. I forgot to check the odometer so I cant tell you how many miles, it was more than 50 and we used two bars off the fuel gauge The "message center" reported the oil at the bottom of the "OK" range
