So I'm driving today and getting low on gas so my computer starts blinking at me telling me I need gas. It started around 57 miles remaining. Got it down to about 25 and then noticed a rapid decline. It went from 25 to 18 in about a mile on the highway and then from 18 to 14 in another mile. Then finally after probably less than a mile it went to the - - -. Is anyone else getting this kind of behavior out of the range feature of the computer? I realize that it won't always be 100% accurate, but to go from 14 to nothing in the span of about half a mile is kind of strange. Also, does anyone know how many miles you have after the ---? I got 370 miles out of my tank which puts me at around 18.5 mpg...not bad, but not great. My commute is about half highway and half city.

 

from what Ive notice there is probably about a 2 gallon reserve in my 13, after the "---" appears.. which usually takes 18 gallons to top off, brochure says tank is 20 gallons...

 

The computer estimate is relative to the style of driving you are doing before the next update is flashed on your screen. If it said 57 and you are driving uphill then the next number to be flashed will be considerable less than the actual milage driven. Same as if you were coasting the milage available will increase beyound the original 57. I find that if driving on flat terrain the milage left is pretty accurate if the is no sudden driving changes.

 

Nissan designs the car to keep 3 gallons in reserve after the range blanks out "Range (- -) Miles"

The reason they do this is because if you run the fuel system completely dry it will damage it and you will need to replace the system. It is a safety measure.

I know this because I have actually ran my gas down to where it is blank, just to see exactly what happens. When I filled it up it only registered 17.1xx gallons.

Again this a safety feature designed by Nissan so that you don't run you tank completely empty. Pretty clever if you ask me

 

Yes as Ehart mentioned it's a reserve because this is a 20 gallon tank. I have a 10' Sport so idk if it makes a difference but I've noticed 3 gallons in my reserve.

 

I must have really ran it down cause it filled up to 18.5 gallons. To keep from damaging the system though, I will probably start filling up when it starts to blink at me.

 

I pretty much drive like a granny

There were really no hills where I was at, but that's a good thing to keep in mind. I will probably just need to fill up not too long after it starts blinking at me just to be on the safe side. I got almost 2 weeks out of a tank with my commute, so that's not too shabby!

 

It could be like Ehart said and be 2 gallons or it could slightly vary across cars, whether because of year or whatever. But yeah I usually fill up at 1/4 tank now. Just waiting for the summer when they take this antifreeze chemical out of the gas so my MPGs can start going back up. 19 MPG on the highway depresses me greatly lol

 

I never wait for my tank to get that low. Around a third of a tank I start looking for a gas station. Keep in mind that your fuel pump is located inside the fuel tank and relies on the gasoline for the cooling, so the less fuel there is in the tank the hotter the fuel pump gets which is not conducive to pump long life.


PS it does not cost more to fill more frequently

 

fill up before you get under a 1/4 tank. i still for the life of me cant understand why people ride to the bottom of the tank. you're not only sucking up whatever sediment collected in the bottom of the gas tank but stressing the fuel pump unnecessarily. as mentioned above, doesn't cost you a cent to fill up more often.

 

Not necessarily. Falling gas prices will save you a little more money if you fill up less often, (Always fill up close to empty) and rising prices will save you a little more money if you fill up more often (Fill up when its close to half).

 

I'll fill the tank 9 times out of 10 when it's half-full and never let it get below 1/4 tank.

Only use premium and only fill up at Shell.

 

This car is not a Honda civic and was not meant for penny pinching buyers
so this type of behavior during falling gas prices may fit the definition of penny wise dollar foolish.

 

False. I mean you're absolutely right about the Honda comparison but you make it seem like this car is a BMW. Premium gas is not required, it's recommended (HUGE DIFFERENCE). While I only run 93 the manual states that 89 is perfectly acceptable and even 87 can be used (at decreased performance). Not saying to use 87 but at the same time I doubt you or anyone of that matter ignores gas prices.. Buying the same gas when it's $3.95 instead of $4.05 isn't being frugal, it's called being smart.. Back to the topic, while this car can be a $40,000 car, this is not an Infiniti, Lexus, or BMW so if you paid that price you got scammed. so again I don't see the issue with people penny pinching on gas prices for a 20 gallon tank.

 

The only time I've let this happen was once in the summer and once during this winter when I was trying to calculate my MPG to the my last fill up because as you know, the MPG calculator on the car is not always fully accurate.

But yes, Shell is the only gas I use. Use to use a Sunoco station by my house as well but the gas station changed to Gulf and that's when I made my sole gas station Shell

 

I was only proving a point where the above poster said it doesn't cost a cent to fill up more ofter. It surely does when prices are falling. Besides whats wrong with being penny wise. There is nothing foolish about it.

 

I was really just curious to see how far I could go on a tank, but typically I'll fill up around 1/4 left. Thanks to all for their replies...good info!

 

In my opinion there are two kinds of people at the gas pumps: those who make multiple stops per week and put in $10 - $20 each time, or those who fill their tank when they're either a.) empty, or b.) have reached their personal threshold for the low-point of their tank.

 

You can't actually run the tank dry. It is IMPOSSIBLE.
The car has a 20 gallon tank. If you run it until the car shuts off and won't start, then fill it up, you can only put in 19 gallons.

This design keeps the pump from picking up sediment and large particulate matter that builds up over time.

 

Good point. Never looked at the reserve tank design like that but that's an even more genius fail safe

 

You are absolutely right. I don't have a personal threshold but whenever I go to the gas station, it's to fill the tank, not add $10 of gas.

 

There is nothing wrong in saving money. However, you completely missed my point. The way I see it trying to pinch pennies here and there to save a buck or so is not worth damaging an expensive fuel pump because you let the fuel tank run low so that the pump start to over heat.

 

Yes you do a have good point in that regard. Maybe I just over thought your response lol. In that case I will give it to you but at the same time I doubt anyone who drives this car runs down the gas because they don't like filling up, can't see people doing that with a newer car in general so it must be for some other reason besides frugalness

 

I fill up once the range starts blinking to --- or ~30 miles. Thats about 17.5 gallons. This "sediment at the bottom of the tank" was probably true in the back of the days or the pump could be easily designed not to suck up crap. If that was an issue than I'm sure that dealers/mechanics would offer a service to clean out your tank. I dont know about the pump needing fuel to cool it either cause as I look at the layout of the tank/pump design the pump is on the top of the fuel tank so that means the last few gallons of fuel(half of the tank?) is not cooling the pump. The only way the pump might be cooled by the fuel is if there is a separate section like a gallon which surrounds the fuel pump. That might be the case cause the gas tank tube(intake) is pointed towards the pump. That would be a smart simple design which could use freshest fuel as a reserve and cool it. http://www.courtesyparts.com/maxima-...8321_8325.html

And to the OP the Range is "realtime" it wont ever be exact cause it cant predict if theres a heavy incline/acceleration in the future that will give you a big mpg hit. Thats true for every car. Its possible to get you a better mpg calculation if it takes into consideration your future road inclines, red lights, traffic, etc but that's something Mercedes or Google would be smart enough to do but Mercedes drivers dont really care about mpgs. Its not worth the trouble to implement that just to get you a better calculation.

 

what's so special about shell gas

 

Vectron

 

location. its the only non cheap gas station convenient to me.

 

Shell gas is in Tier One gasoline's along with Chevron, BP, etc. Google it to see the other companies that are in tier one. What is special about them is that the government dictates the minimum amount of additives that needs to be used in gasoline's and that is what you get in unbranded gas stations. Tier one gasoline's however exceed the minimum government standards and keeps the engines cleaner. In fact I only use Shell 93 Octane on my turbo- charged BMW.

 

Good thread. Having driven for 65 years, I have encountered several situations that showed very clearly why driving the tank low is indeed 'pound foolish.'

Many years ago, I left a small town in west Texas, headed west to Arizona, knowing I had plenty of fuel to reach the next town around fifty miles away (nothing is close to anything in west Texas). I arrived at that town after a storm had come through, knocking out power. No power, no gas pumps.

The next town was around 60 miles away, and I was down to a around two gallons. I ended up having to spend the rest of that day and all that night in a motel (with no lights, hot water, heat or AC because of the power outage) waiting for the power to come back on. All because I let my tank run low.

That taught me a lesson. When out in open country, don't let the tank run low.

But I still tended to let the tank run low when just jockeying around my local area. Until we had a major lightning storm that knocked out power, phones, etc in my whole area. Again, I was low on fuel, had no idea where the nearest station with power might be, but also knew stations just outside the outage area would probably run out of fuel very quickly.

Again, I was stuck at home (without lights, heat or AC) because I foolishly let my tank run low.

Most service stations these days have a large cover protecting folks who are gassing up from the rain. But if a storm is passing through, the wind blows the rain inside the cover, and I have gotten rather wet trying to fill up during a storm (as well as wondering if lightning was going to turn me to toast). Just another reason to have filled up before the tank was low.

I begin thinking of refueling as soon as I am down to a third of a tank left, and become very serious about it once I am down to a quarter tank. Young folks may get a thrill from living on the edge, but us old folks have already had enough thrills for one life.

 

Just got back a few weeks ago from Florida. I drove down and back.
On the way down, I was in an area that I thought had gas stations. My last fill up, premium was around $3.65 or so. The range indicator started blinking, so I pulled over to the next station. They wanted $4.09 per gallon of premium. Why? Because they were right by the highway. I don't like being robbed, so I kept going. Long story short, I watched the range drop quickly and then show ---. The wife got scared. I kept going until the next gas station, where they were charging $3.69. I filled up, but only got 18.5 gallons in.
Like all cars, "e" isn't really empty. I was averaging around 23 mpg, so I could have gone another 30 or so miles before I had a real situation on my hands. Car manufacturers don't want you to run out of gas because of some of the concerns already brought up. I usually fill up the moment my range shows less than 100 miles at the latest.
But to answer the original question: it isn't accurate. Neither is the MPG. The computer is guessing and it's not nearly complex enough to be very accurate. It's close enough for rock and roll, but determining actual maximum remaining range, it would need to do real time computing very quickly.
I agree with many: don't try to find out. I usually fill up when I have 1/4 tank left.

 

^If you put in 18.5, then you had less than 12 miles left at your usage rate.

 

I would have put in $10 at that first station and spend the extra $1 for increased price. That way I would have at least another 50 miles guarenteed driving distance. $1 for peace of mind is a good deal. Shoot even if you filled up at the first station it would only cost and extra 6-7 bucks. Alot better than being stranded on the highway.

 

im only getting about 220-240 miles per tank. is this normal? 50/50 hwy/city. it does feel like a very slight misfire at idle. i think plugs.???

 

I get 400 per tank, 80% highway, averaging 75mph.
Driving the speed limit only, I get 450 miles per tank.
Driving like an ***, I get about 300 per tank.

09 with 95k miles.

 

i have an 03 nissan max 5th gen 6 speed with 120k

 

Your 6 speed plus city driving equals low milage. Add to that if your plugs are original, they need to get changed. I had a 5th gen GLE (auto) and got 23 city/hwy and almost 30 straight hwy. If you are putting in about 15 gallons per tank then you are getting around 15MPG, not good.

Plugs, tuneup, are in order and keeping your foot out of it with a 6 speed is hard to do.

 

yeah i put about 16.5 gallons of super and still. i did an oil change with filter, im going to try and get the plugs and pcv valve changed and see if it helps. is there anything else i should do?

 

Similar thing happened to me. I was heading to the opposite end of FL on I95. I was in a rental Maxima and had over a quarter tank and one of my tires was low on air. It was prob 12AM. So I see the gas station signs on I95 but they are not lit up for some reason so I got off at some small town and drove over 5 miles west of I95 to some chevron and boom it was closed. So I learned that night that when the signs aren't lit up that means the station is not 24/7. I wasn't low but that was a big waste of gas and time to end up at an closed station. Didn't have change so I couldn't even put air in the tire.