Trip Computer Question (gas mileage)

[Steve491]

How does the on board trip computer calculate gas mileage? It's miles per gallon and I know how the car knows "miles". How does it know gallons? Is there some sort of sensor on the fuel line that measures the volume of fuel or does it use the duty cycle of 8 stock fuel injectors? Anyone know?

 

[Hoowasat]

It knows how much fuel is sprayed through the injectors.

 

[SpartaPerformance]

It knows how much fuel is sprayed through the injectors.

Correct it keeps track of injector pulse

 

[Steve491]

Lets say for example I modify the car with different fuel injectors and/or rear end gears. Of course the computer will be flashed to reflect these changes. Do you think the onboard trip data will be correct? After all the handheld tuners just "hack" the Ford program. Any thoughts?

 

[Hoowasat]

(deleted ... i was rude)