Case Study: 2009 Corolla 42 MPG at 58 MPH

This Real World Vehicle Efficiency Report is on a 2009 Toyota Corolla S rented for a trip in December 2008. This roomy, well appointed 4 door sedan is powered by a 1.8L 4 cyl engine with a 4 speed automatic transmission. It is an Ultra Low Emission Vehicle II with an EPA estimated MPG of 27/35 and a starting list price of $15,350. It has a dashboard computer that monitors, records and reports MPG data and the odometer includes A and B trip recording. I topped off the tank, zeroed everything and set the cruise control at a notch or two over 55 MPH and over the course of 1,523 miles averaged 42.23 MPG, a 22% savings over the EPA estimate.

Going South from Sacramento I took I-5 to LA and then I-10 East to Phoenix. When I arrived in Phoenix and topped off the fuel tank, the dashboard computer reported an average 45.2 MPG and avg. speed 52 MPH. Elapsed Time was 14:03 to drive 749.8 miles. In Ontario, California I refueled with 10.454 gal and when I arrived in downtown Phoenix I topped off the tank with 7.440 gal for a total of 17.894 gal.

749.8 miles / 17.894 gal = 41.90 MPG.

I drove around town for 4 days, 256 miles on 10 gallons, for an avg of 25.6 MPG

Returning from Mesa, Arizona to Sacramento California via I-10 to I-5 in LA then north merging onto HWY 99 to Sacramento this journey included mild to heavy wind, rain and some brief snow over the Tejon pass outside of LA. When I arrived in Sacramento the dashboard computer reported an avg 45.1 MPG and avg. speed 52 MPH. Elapsed Time was 14:46 to drive 773.8 miles. I refueled in Newhall, CA with 10.245 gal and topped off in Sacramento with 7.926 gal for a total of 18.171 gal.

773.7 miles / 18.171 gal = 42.57 MPG. 

Fuel receipts add up to 36.06 gallons for the round trip of 1,523 miles = 42.23 MPG. Based on the EPA estimate for this car of 35 MPG I would have used 43.51 gallons so I used 7.7 gal less fuel, a 22% improvement over the EPA estimate.

35.8 x 125,000 = 4,475,000 btu / 1523 = 2,938 btu per mile
43.5 x 125,000 = 5,438,750 btu / 1523 = 3,571 btu per mile
Difference = 22%, 7.7 gallons, 633 btu per mile

Data sources:

• RWVER Dec 10 - 15, 2008 by Tim Castleman
• http://www.toyota.com/corolla/specs.html
• http://www.fueleconomy.gov
• http://en.wikipedia.org/wiki/Fuel_efficiency