What mechanical/software elements are involved in ascertaining the Miles per gallon in a motor vehicle?
2007-03-22 13:30:41 · 5 answers · asked by cover_now_or_perish 1 in Cars & Transportation ➔ Other - Cars & Transportation
Your car has several sensors that work together furnishing an input to the trip computer to give this answer. There is a gasoline usage sensor which gives gallons being used for a given period of time. At the same time, there is a sensor sending pulses from your transmission/drive train which converts directly to miles traveled during that same interval of gas usage. Put them together and you get miles per gallon. This is a variable that flucuates wildly when in traffic, (accelerate -bad millage, coast- good miollage when going down a hill, stop-no miles traveled but using gas to keep the engine running and any airconditioning and electronics running) The computer averages all these together over a period of time and gives you a miles-per-gallon. On the open road with no variations, the miles-per-gallon is better because the engine is performing at a steady rate. Keep running at the legal speeds also will show better millage. Careful monitoring of the miles per gallon rate will show you what it costs to run the air conditioning, which gas gives you better millage, which oil really give better millage, what a badly running engine costs you in millage, how much does it cost in MPG to pull the trailor. Even putting your hands out an open window may show in millage variations.
2007-03-22 13:53:31 · answer #1 · answered by Brian T 6 · 1⤊ 0⤋
The simplest system measures 2 things, mph and gph. Miles per hour are measured by the speedometer system that all cars have. The second one is gallons per hour which can be measured by a simple flowmeter in line with the fuel line from the gas tank. Flowmeters measure fuel flow and convert it into digital form for computers to evaluate. The computer simply divides mph/gph= mpg. Computers can do this many times per second and give instant mpg readings. It can also average the readings to give your average mpg over a long trip or even many days.
2016-03-17 05:12:36 · answer #2 · answered by Jimmy 1 · 0⤊ 0⤋
It is all software. The computer calculates the vehicle speed and how much fuel the injectors are dumping into the cylinders and produces a number based on those two factors.
2007-03-22 13:37:20 · answer #3 · answered by maybayus123 3 · 0⤊ 0⤋
The gauges are programmed to show a pre-callibrated mpg read out at certain RPM's
2007-03-22 13:37:16 · answer #4 · answered by Will L 2 · 0⤊ 1⤋
gps?
2007-03-22 13:37:53 · answer #5 · answered by noskillzorz 2 · 0⤊ 1⤋