I drive a 94 Camry which still works great after 180K miles. I've been record the gas gauge reading trying to know fuel efficiency in the past few years.
I'm a little puzzled on how it works and the accuracy of the reading. My observations: I suspect the sensor is in the front part of the tank as the gas level drops when you climbing up the hill, and goes up when driving down the hill. The level goes up and down sometimes. In the middle of the driving, it may go 1 to 2 mm below and it would go up again a few minutes later. Maybe it relates to the condition of the road? The level usually drops (and not coming up again) at a bigger distance than a gradual drop. I may stay on full first. going down and up a few times, then it drops to 2/3 above the next scale down. The level location may be the most accurate when you first start up in the morning. Usually it's a little lower than the previous night. But it will go up again similar to the previous day due to moving. I suspect the temperature makes a difference too.
So basically, it's hard for me to really know how much gas I've used daily thus the MPG, and how much gas exactly is left. Are there new cars that provide more accurate reading, something similar to MPG indicator in some of the cars?
Thanks,