Terry Shea, writing for AOL Autos, attempts to explain the mystery of the inaccurate gas guage:
Have you ever noticed that your gas gauge stays on full for quite a while before the needle even moves and then it moves faster and faster as it approaches empty? And then when it gets to “E” it sort of stays there for a while until the low warning light comes on …?
It turns out it’s partially your fault that gas gauges work that way.
The engineers calibrate them to do that. Why? Because you, the customer, have told them that’s the way you like it. We spoke with Phil Pierron, an engineer at Ford (his title is actually “Technical Expert for Systems Engineering in Core Fuel Systems), who told us, “Our customers really didn’t want to run out of fuel when they hit ‘E.’ Customers do want some amount of fuel when they get to ‘E.’”
Apparently, consumer surveys indicate that people don’t like seeing the needle depart from “F” right away either ... . According to Pierron, “Customers want it to say on full for an amount of time.” This gives them the illusion that they are getting better fuel mileage or at least not immediately burning through that expensive tank of petrol they just bought, even if they quite literally are. …
And while customers want there to be a “reserve” of gasoline available when they reach the empty mark … they don’t want too much of a reserve. Otherwise, they will complain that their 20-gallon tank only takes 15 gallons when filling up from empty. Apparently, there is a sweet spot where customers are happy to be fooled by their gas gauges, but not too much. We customers sure are a fickle bunch.
The engineer’s job should be to make things more accurate and efficient, but in this case he has to play psychologist to keep customers happy.
Most people have a complicated relationship with the truth. They think they want the truth but bulk when it gets too uncomfortable. The problem is God's promised blessings are all predicated on our willingness to heed the truth.
"If we claim to be without sin, we deceive ourselves and the truth is not in us. If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness" (1 John 1:8-9).