So I got curious.
Ive never driven at 70-75 for any long distance.
So I went for a test.
I hooked up my laptop to the OBD II port.
Gassed up the tank- let the gas pump shut off on its own.
Reset the DIC.
Took the streets and I got on the freeway. Intent was to hit 75 and stay there. But due to traffic a few times we slowed to 45-50 for a few minutes.
but then Id get back up to the 70-75 range. After 30 min of driving I got off the freeway- and took some streets to get back on in the opposite direction.
There is a hill I had to climb in both directions. For this- I head over to the slow lane- and drive up at about 60- on the way down- the trans is in L and 6 so as not to engage descent control. (engine braking).
Once I got off the freeway- I headed straight to the same gas station and used the same pump I used when I started. Once I parked at the pump I stopped the laptops recording data.
Here are the Results.....
TRIP- 69.2 miles
DIC Gal used- 2.7
DIC MPG- 25
AVG speed 62.7
At the PUMP
GAL PUMPED- 2.66 (I let the gas pump auto shut off).
Hand calc MPG-26 69.2 miles/2.66 galons=26.01 mpg
cost to refill=$9.48 (@$3.55 per gal of regular).
Now heres the amazing part.... see the numbers below.. of the data gathered from the OBD port.
It calculated I used 2.66 gallons--- same amount that the gas pumped AUTO shut off- and very very close to the DIC.
It shows 25.95 MPG-- I calculated 26 vs DICs 25
Total trip cost... $9.43 as per laptop..... I paid $9.48.
It shows 68.9 miles traveled as compared to DIC 69.2. pretty close to what the DIC showed.
Conditions--- only me on board. No AC. Outside temp 55 deg.