Is three quarters of a tank really three quarters of a tank?
 

Well, been sipping my little VX on its first full tank. Been using googlemaps to keep track of how far I've driven. So far I've driven 184 miles in mixed driving (no interstate) with a top speed of about 60mph but a mean speed of about 45 and the gas gauge is hovering about halfway between the full line and 3/4 full. I've done a some ICE off coasting in neutral but not as much as I could and not all the time. It's a 10.0 gallon tank. What kind of mileage am I getting so far? I find that on most cars 3/4 full generally isn't 3/4 full (usally less).... What have other VX owners noticed about their gas gauges? Right now the gauge bobs from just below the Full line to just a little less than 7/8. It hasn't actually reached 3/4 yet. But even assuming it's at 3/4 full now, that means I'm looking at 736 miles or 73.6mpg for the entire tank. Is this possible? Or is my gauge lying to me? I did top off the tank about $.40 @ $2.67/gallon which is about 0.15 gallons. I think the car was pretty level when i filled it. Everything is stock on this car. Except the tires which I don't think are helping its case any.... the fronts almost look like snow tires. I guess I should wait till 1/2 tank before getting too excited. :D

Hmm 73 seems a little high for how you are driveing it would take alot more to get that, im not saying you cant with that car but im guessing your around 45-55 range. Do you have a trip botton that you can push that will count your miles? This would be alot more close to actual miles so you would know for sure.

3/4 of a tank is definitely not 3/4 of a tank. Not on any car I've owned, anyway.

I have yet to see a car with a linear gas gauge. Tanks generally have very irregular shapes to them plus the floats only go so far within them. Mine shows empty even though it has 15L/4Gal left.

Try and take note how far you have gone when you hit each major marker on the gauge and then you can gauge the tank from that.

xx miles down to where you are even with the full, at xxx miles you are at the 3/4 marker, then ?, then ?...

Then you'll have some reference as to how well each tank is doing.

DAMN right your gauge is lying. The first time I drove 98 Camry I almost let loose in my panyts I was so happy. It took over 80 miles for the needle to go below the F marker. I thought the needle was broken prior to that. Now that Im driving for FE I can get over 100 miles and you will not even know that I drove the car according to the needle. I makes NO MOVEMENT. I guess its like a 3 gallon "OVER-reserve". Those needles can be used as a reference for someone who KNOWS the car already. Dont be fooled by first tank

Ha ha. GOOD LUCK!! You should wait for an EMPTY tank. Once again my high tank of 685 miles in '98 Camry' had hit over 400 miles at half tank, but didnt get anywhere near 800 miles. I expected that but had it been my first tank and I didnt know any better I would have been pissed to be at 415 miles half tank only to get 685 miles at the end of the tank (and that was with nearly killing my reserve. I find that my first half generally gets me about 100 miles more than my second half tank, if I were to go by the needle. I dont want to be pessimistic. Im sure you mpg will be good, I just want you to finish a tank forst for a good reading.

I don't know for your VX, but my VX cauge is completly wrong. Espacially the first half. If I fill it up completly, I might be doing 60miles and more before getting lower than the F. And I'm pretty sure its a 11.9 gallon tank we have.

BIBI, if you have a stock tank, its 10 Gallons.
The gauges aren't linear. I can usually get 100 - 120 miles before my gauge comes down to the full mark.

Hum, maybe but I rembember having putting a 40 liter one time, and yes its stock, but anayway doesn't really matter I don't want to start a thread on this you might be right. But yes 47-48 liters seems high. And its also a 1992 gauges with the technology of that time so I don't have a lot of espectation about the precision, from the moment I'm not near below the red line :D.

Thanks guys for weighing in. It dropped drastically this morning, as if just because I had opened my mouth. It's now between 2/3 and 7/8. But, yeah, it seems the gauge is pretty unreliable. I'm now at 199.3 = miles at "3/4" tank. I'm projecting 340 miles when it has settled in on the 1/2 way mark and 580 by the time I'm not willing to drive anymore before filling up for fear of running out of gas.

Hockey4mnhs: my odometer doesn't work 1/2 the time so I have to rely on googlemaps. I think it's fairly accurate. If anything I'm driving more as it doesn't take into consideration parking lots and driveways.

THIS post has a discussion on the civic gas gauge for reference.

my gauge does the slow first half tank then really fast on the last part also it might be a honda thing also??

Thanks TomO, that link was quite informative. I found that in my '85 Accord that half tank was pretty close to being an actual half tank. I think I like DaX's approach the gas tank:

I also can relate to the original poster's comment, as I had the same experience with my '85 Accord and with this VX.

For instance, my tank dropped drastically the morning after I started this thread.:p

Gas gauges are gas guesstimators!
 

Nope. It's pretty universal from my experience.
Both my Tahoe and my Saturn get most(about 2/3+) of their miles out of the "first half" of the gas tank. Once they hit half the gauge drops like lead bird poo. Same deal with my Explorer I sold this spring. My Tahoe has a 30 gallon tank and only takes 25 gallons when on "empty". :rolleyes:

Yeah, my gauge is rapidly headed toward half tank as I come up on 250 miles.

ive gone almost 80 miles on the first "quarter tank" but i usually get about 250 a tank, i doubt my gas mileage has improved that much :p

The gauge is not unreliable, it's just inaccurate. It will act the same way on every tank. It's purpose isn't to let you know how many miles you've gone, it's to tell you when the tank needs filling again with a rough estimate of how much you have in there. For this use it's very accurate, because it tells you that you have a little or a lot of gas, and tells you when you need to fill the tank. Run a few tanks through and you'll get a feel for it.

I honestly wonder this at times.... Gauge spent less than 50 miles a smidge below the F line to falling to just above half tank after spending 185 miles at the F! All cars do this to some extent but this VX seems significantly worse than other cars I've driven as far as drastic gauge changes.

haha, no. right now im reading just over half tank (mabye a gallon) and im at 95 miles. i dont pay attention anymore until its time to fill up. ive just used "a quarter tank" for 20 miles. not even i get that bad gas mileage. haha.

Well, I've hit a 1/2 tank and am at 295 miles. Going to Worcester today (I'm on the Mass/New York border and Worcester is 30 miles west of Boston. It's about 100 miles each way. So I should be able to get out there and back home again before needing to fill up. That would take me to about 500 miles. We shall see.

In Worcester with 435 miles now. Gas gauge is still above 1/4. 600 miles may just be within reach. Although I may fill up here in Worcester as gas is twenty two cents cheaper. Drove 80 miles on the Mass Pike at 65mph most of the time, dropping to 60 during neutral gear "glides" down hills (engine on) and 70+mph my upper end. The speedo and odometer worked the entire time on the highway. It seems once the car has beening going for awhile it isn't so buggy. But when the engine is cool? or dinking around town it not working for much of the time. I dragged for a total of about ten minutes behind a truck toward the end of the trip. 550 miles at least seems very possible. Rear tires were underinflated this whole time. Put them up to 46 PSI Right before I left to Worcester. They were at 39. They're rated at 44. The fronts are rated at 35 but had also been at 39. So I left them there.

Drove out to Worcester on the highway at 65mph and engine on coasting down the hills to 58-60mph before accelerating back to 65-70mph. Filled up right before I went back home because the gas was $2.579. Took less than 8 gallons with topping off. Average for the 449 mile tank was a little over 56MPG. Not as good as I was hoping for but considering the rear tires had been underinflated and the fronts are only rated to 35psi... and the high idle when warming up and all the stop and go driving and idling at stoplights etc... not too bad. I drove the first 80 miles of this new tank at 75mph so I'll prolly not be able to get 60mpg for this tank either, but we'll see.

About tire pressure. How much over the max sidewall PSI do people inflate their tires? I see some people on here have them as high as 60psi. Are there tires that are designed to be inflated this high or are people inflating them over the max sidewall psi?

people are exceeding the sidewall rating.

You can't go wrong looking at old posts by krousdb.
https://www.gassavers.org/showthread.php?t=803

I know with my VX I would often go 120 miles before the gauge moving, and then it would stick at 1/4 tank until about 230 miles, then at right around 250, it would go to half, or lower.

Out of all of the Hondas I've owned, my VX has the least accurate gas gauge. Maybe b/c it also has the smallest gas tank? I don't know.

Ok, I filled up my car when the gauge got to E but it only took 7.9 gallons before spilling gas all over the place. The thing is I had the nozzle in the gas tank upside down because I was stretching it to the wrong side of the car (I had the gas tank facing the wrong way) Was my tank actually full or did it overspill because I had the nozzle in upside down? I was taken by surprise when the tank overflowed because I was expecting to go to 9 gallons. 530 miles on 7.9 gallons means I got 67mpg. While it's not totally unthinkable, compared to my last tank of just under 57, that is quite an improvement. Although this tank I didn't have any fuel system cleaner which apparently makes the gas burn quicker. I'm thinking if my gas gauge doesn't budge for the first 50 miles, then it was all the way filled up. If it wasn't filled up, it should start dropping soon. Wish I had filled up properly so I wouldn't have this ambiguity. What does anyone think? Does having the nozzle in the gas tank upside down cause premature overspillage before the tank is full?