I mentioned in another thread that I had recently gotten a Bluetooth OBD II reader and Torque Pro for my Android phone. I had played with it a couple of times but hadn't really put it to the test. I finally did that last week on an 850 mile trip pulling a loaded U-Haul trailer.

When I first started out, I got on the interstate and set the cruise control on 62. At the end of the tank I had averaged 13.6 MPG. Not horrible but on my last trip pulling a trailer I averaged 16.5 so I knew I could do better.

On the next tank I didn't use the cruise control but adjusted the throttle manually while watching the output from Torque Pro. I immediately saw a huge difference. You can see on the image that I am 615.9 miles into the trip at this point. The average MPG for the entire trip at this point is 17.9. The bottom right box shows that I am 100.8 miles in on this latest leg and am averaging 20.1 MPG! And this is with a loaded truck and trailer!

For the past few days I have been using Torque Pro around town and have upped my in-town mileage from just over 16 to over 20.

 

Very cool. Are you improving your mileage jsut by altering your driving style?

 

When you were on the highway, was you going up inclines where the Hummer kept shifting itself into a lower gear... I find that its best if you manually give it the gas if you are on hilly roads...

 

Yeah, it was all about driving style. Pappibri, I drove from South Texas to North Georgia. The first tank where I got the worst mileage using cruise was actually the flattest. But the cruise control stays into the throttle all the time it seems. The increase came by accelerating/coasting/accelerating/coasting. I had 850 miles to play with the driving style and finally got it down pretty good. At first I thought I should coast downhill where the weight of the truck would carry it. I actually learned that I need to accelerate down hills and get enough momentum to carry me up the next one since that is the place that you use the most fuel. As long as traffic is light I can do pretty much what I need. Since I dropped the trailer, I took one short trip the other day and went 60 miles on just over 2 gallons of gas. I don't feel like I am driving all that much slower, just different.

 

One thing remaining is to confirm the millage shown by the tool with the calculations from the pump. Have you confirmed the numbers?

Thanks.

 

Agreed.

However, the PCM does display a pretty accurate almost real time fuel consumption rate based upon the fuel injector pulse times. The question becomes how accurate over 300 - 600 miles? For that you have to look at the pump as well.

The Scan Gauge can do the same thing with lower tech. I had 22.4MPG the other night in cool 58F temp, no wind, and 50MPH on the way up the nice and flat lake shore timing the few lights there are.

Lower tech even yet, any of you old enough to remember the old cars (70s Bonneville for one) that had the vacuum gauge or economy lights that you could watch while driving? Basically stay out of and be easy on the pedal, and fuel economy goes up, but no display as to MPG while you are doing it.

 

I've run Torque + BT and using the gas mileage from the computer is pretty close to what goes in at the pump. I'm guessing I've run a dozen+ tanks where I was comparing the two and it was close enough I trust the computer now

 

...and I just realized I've been a member on here for 4+ years and just exceeded my 'maximum of 2 posts per year' quota