Just got my 2008 Prius a little more than two weeks ago. I bought it used with only 9k on it. Last Saturday I filled it up for the first time. Since then I have driven 120 miles but the gas gauge still shows "full". I admit that I did top off a little, did I do any damage? Why does the gas gauge seem to be stuck? BTW, I'm averaging 57.4 mpg so far, very happy! Thanks!
I frequently take over that to go down one pip, but once it starts, it loses a pip about every 40 miles. Sure would have been nice if each pip had been about one gallon.
You answered your own question - topped off and 57.4 MPG. It will drop to 9 pips soon. Careful on the topping off, don't try to fill the pipe. BUT, do get to know the quirks of your car and the stations you use. Some pumps will kick off WAY early, some about right and on rare occasion, they don't kick off. Your MFD MPG will likely be off a bit. Mine reads about 1 MPG high, my wife's about 2 MPG high. Keep that in mind and before you fill, figure out how much you SHOULD be able to put in. If you drove 500 miles and the MPG says 50, you should be able to get about 10 gallons in. If it kicks off well before that, you can add more. My car starts flashing the last pip when I have used about 9.5 gallons but all cars are different.
Gas gauges are biased that way. Think about the driving implications: Essentially there is no difference between full and nearly full, but there is a big difference between nearly empty and empty. Because of this the gauge is calibrated at the low end, which often means some dead space at the top. It's normal. Tom
I've given up trying to measure what's left by looking at the Pips. I fill up every 300-325 miles regardless of what the Pips show. It doesn't cost any more to fill up more often.
If anyone has a Scanguage II there is an Xguage that can be easily programmed to measure the gas guage in digital number form. I've run 4 tanks so far since installing the Xguage Gas function and it seems to be fairly close to accurate (although I'm not going to run it down near 0 on the SGII to find out. With 1 Pip left the digital readout was 12.5 remaining...which is a percentage...so it's close. And the number counts down in 2.5 segments so there is probably an error margin around +/- 5.0
When the first pip disappears is something I track (I'm so ashamed to admit I do this). It's varied between 109 miles (on a 44.4 mgp tank) to 144 miles (on a 50.2 mpg tank), suggesting that the first pip on my car represents somewhere between 2.5 and 2.9 gallons of gas. Subsequent pips seem to indicate something like 0.8 to 1.0 gallons each.
Makes perfect sense, my first pip finally dropped today at 170 miles. Very valuable info for a newbie. Thanks!