Ever wonder what’s really going on with your fuel gauge? Do you often feel like it’s not giving you the full story when it comes to how much gas you’re actually using? If you’ve ever pondered these things, you’re not alone. The answer to the aforementioned questions is that there really is no decisive answer. One thing’s for sure, the fuel gauge has been a constant source of fascination, especially in recent times, when gas prices seem to jump at the slightest hint of political or economic uncertainty.

Quirk or conspiracy?

The truth is that fuel-gauge performance can differ from make, model year and even in individual cars within the same model group. Automotive designers and engineers have periodically come forth to enlighten us on the thought processes behind the gauges, and even those vary from person to person. One example is the digital fuel gauge. Turns out, when digital gauges were first introduced within a specific automotive line, certain sectors of the public got confused when it flashed a number representing how many gallons were left, not long after showing the tank as “Full.” Some car owners read this as a sign of poor mileage, even though the gauge showed that it was still almost full! The solution was for the unnamed automaker to re-program the gauge so as to not veer too far from “Full,” at least for a few more miles. The complaints soon dried up….go figure.

The mysterious case of Mr. “E”

Questions also arise in regards to how far you can actually drive when the gauge shows that you’re on “E,” accompanied by the requisite bright light. Like so many other fuel-gauge issues, the answer is that no one can really say for sure, as each individual car has its own set of issues and quirks. Some vehicles will still have a couple gallons left burn, while others may run for dozens more miles. The only real way to know for sure is to keep driving past “E”—with a freshly juiced gas can at the ready. But, that’s only if you’re losing sleep, or have absolutely nothing better to do. (Note: It’s not advised performing this test on older vehicles as their weathered tanks may be laced with things like dirt and water that you definitely don’t want your car ingesting uncut.)

As you ponder living dangerously, check out these useful fuel-additives and accessories to keep your car’s tank in shape.