On 7/20/2017 3:52 PM, trader_4 wrote:


The readout on the computer still says 25 even though you only get 23.
Sort of like saying if you had pure gas this is what you;d have gotten
but you got something else.

I don't see how the computer readout will still say 25 even though
you get 23. Like DPB said, the car computer is simply computing
miles traveled by volume of fuel injected. With the lower energy
content gas it will have to use more gas to go the same distance
and the number calculated will show it. Instead of 25 mpg, you'll
get 23. Take it to the limits. Suppose you had gas that had very
little energy content and a gallon could only propel the car 1 mile.
What would it show? 1 MPG or 25 mpg?


The translation I get from GM is that it will read 25. Makes no sense
to consider energy per gallon but it seems they do. I look at it as a
rough guide, nothing more. When I turn my car off I get a reading from
the last trip. Highway will be in the 25 range, city will be in the 18
range.