Ron A

When I picked up my new TL, I topped off the tank so I could get an idea of gas mileage, etc. When the nozzle shut off, I was able to get another gallon in by squeezing the handle many times. It took so long that I quit trying to get any more in, thinking the tank must be full by this time.

I went on my first trip yesterday. On the way home, the low fuel warning light came on and the MID said 47 miles to empty. I think there was another thread here that said you had 3 gallons left when this happened.

I pulled in to the gas station with 10 miles to empty showing on the MID, and total miles for this tank was 405.3. The nozzle shut off at 13.8 gallons. It took a while, but by coaxing I got three (3) more gallons in. The total fillup was 16.818 gallons. This gave me an average mpg of 29, which is what the MID said.

From this, I come to the conclusion that there is only about 1 ½ gallons left in the tank when the low fuel warning light comes on, and depending on the driving conditions you could go between 30 and 44 miles until empty.

Now that I am starting out with a complete full 17 gallon tank, I will wait and see what the results are when the low fuel warning light comes on again and chart all the statistics at that time.

Has anyone else had any experiences like this or done any tests, or am I the only anal retentive TL owner?

VTEC=happiness

This topic actually has extensive posts around the forum....I believe the popular conclusion is that once the Miles to Empty says 0, there is actually almost 3 gallons of gas left. When I hit 0, I actually have driven more than 50 miles before fill up and I still wasn't quite at empty

Pug

Wow - how did you manage 29MPG? The best I've done so far (highway) is 24MPG. My City MPG is around 14MPG.

It's interesting about the top-off issue. I haven't experienced it personally, because I live in a state that doesn't allow me to pump my own gas

My last Honda was a 94 Accord - and I never tried to top it off because doing so almost always resulted in a spill. I was talking to my local service station guy about it, and he commented that he never tops off Hondas for that reason.

My experience with the Honda was that the fuel guage was virtually useless, I'm interested to see how it works out in my TL.

Chitown-TL

Don't know if this applies to Acura's or not but not a good idea to over fill, could cause problems with emission system if gas backs up to the EGR.

You don't need to run the gas tank down to empty to figure out gas mileage so IMHO squeezing in some extra gas is not a good idea unless you are in the middle of nowhere and gas stations are few and far between.

Ron A

What I meant was that I topped it off because I didn't know how close to full the dealer got it when he filled the tank, so I wanted a known starting point. I know you don't have to run it down to empty to figure gas milage, but you have a good point about the emissions. This was just getting to know my new car and finding out at what point the low fuel warning light comes on so I can estimate how many miles I can go before I hit empty.

VTEC: This is the part that puzzles me. I believe what you said, but if there are 3 gallons left when the MID says zero, and I put 16.8 gallons into a 17 gallon tank when my MID said 10 miles to empty, then something is wrong somewhere. I thought about the pump not being accurate and overcharging me, but then my average mpg figure would have been lower. Maybe this particular pump had a nozzle that shut off early and was very sensitive. Will see what happens next time.

Thanks for the feedback, everyone.

VTEC=happiness

Sorry, I didn't catch that you filled up 16.8....very interesting. I have never even put that much in. Perhaps the pump was off, or maybe Acura made the meter more accurate with later builds. Look forward to hearing what happens during your subsequent fill ups.

jtruman

Do a quick calculation whenever you are uncertain. Using the trip computer, find how many miles you have driven since you last filled up and the fuel efficiency in MPG. Divide MPG into total distance driven will show you how many gallons you have used.

Yesterday when I was at the gas station, 330 miles / 22MPG = 15 (use the "calculator" under the Navi system!), and sure enough, I topped off at 15.05 gallons.

The tank is 17 gallons. By use this method, you always know how many gallons you have left.

jtruman

That seems low... see this thread
http://www.acura-tl.com/forum/showth...threadid=71379

AirlineMuseum.c

Probably the best way to do an accurate MPG calc and get the right fillup each time is to start with less than full, and fill it letting the thing automatically shut off and NOT trying to top it off - don't even add a drop more. Reset your trip counter and drive for a while. When you are ready to fill it up again, go back to the same gas station and if possible try to use the same pump. This will take pump auto shutoff variances out of the equasion. Now just fill it up until it auto stops and the tank should be at exactly the same level as it was the last time you filled it. This tells you that however much gas you just put in is exactly how much gas you burned since you last filled up. Divide the number of miles on your trip odometer by the amount of gallons and you have your mpg.

Then use that a few times to calibrate the accuracy of your MID MPG meter and use that. Clearly becuase this method requires you to go to the same gas station each time, you're not going to get very accurate highway only MPGs, but the MID will be very accurate once you calibrate with this method.

R11S

As a soon to be owner (First of April?), I have not read the owner's manual yet and was not aware that the MID could be calibrated. Do I understand this correctly?

KilroyR1

Don't forget, the tube running from the gas tank to the filler has the capacity to hold some fuel. That could throw off the theoretical max fuel.

Don

AirlineMuseum.c

R11S:
Sorry if I was misleading - I didn't mean that you can actually make adjustments to it, but you can see if it is off and if so by how much so you can mentally adjust any results it might provide.

Actually, though I did read on here a way to calibrate the outside temp sensor +/- 3 degrees - you might want to do a search on that. As far as I know it is the only thing that can be adjusted in the MID


DON:
Regardless of how much fuel that tube holds it will always be constant and it will always cause the automatic shutoff when filling to happen at the same time, so that tube should never affect my method.

rets

I'd believe AirlineMuseum.c he's saying you can do the better calculating for yourself. If you like make your life harder, you can¡K

Acutally, I'm doing the similar thing all my life. I always let the nozzle automatically turn-off, after 5 seconds, try again, 5 sec, try again, after the total turn-off three times, I assume my tank is reaching to the almost unanimous FULL level, no matter which gas stations you go to¡K then, I do my math¡K

You cannot re-calibrate TL's MID though. So far IMO I don't know...



TO Ron A, please don¡¦t think of any wrong-doing by this design. Lots of car makers, especially American brands, do the same setup. The only complaint to this early fuel warning system is that you only drive 3/4 tank and have to be gas stations frequently. However, it does help you prevent any further damage to your engine due to the low fuel situation.

You could think the 1st Fuel Empty Warning light is to tell you that the tank may have 3-5 gallons left. The Mileage to Empty is the 2nd warning, 2-3 gallon left¡K I ever accidentally put 16 gallons into my car when spending a long time to search for gas at night, it should not happen again.

Please try to search other threads, you may discover more you wanna know¡K

Norse396

400+ miles for a tank, damn I'm lucky if I get 300...

rljones

To calculate mileage, I've simply zero'd my odometer, and never topped off. Whatever the tank holds is immaterial, as the auto-stop on the pump (especially if you fill up at the same station) is a constant error, and can be ignored. By using this method, the mileage is simply the new miles driven/number gallons pumped until it stops.

You just want to fill the gas to the same relative level, so you know what was consumed. If you top, you're going to create a greater error in your readings (maybe as great as 3 gallons from the above description): for example, 375mi/16gal = 23 MPG, whereas 375/13 = 29 MPG. If you factor in many of the other variables that affect mileage (such as tire pressure, road conditions, wind, accelerations and heavy traffic), and then you compound the uncertainty with topping off, it will be difficult to get a handle on your true mileage.

rets

When you zero your odometer, did you mean to reset "trip computer's info" or A/B mileage odometer?

(I know, for most of ppl, filling up the gas is just feeding up your car, nothing more. Don't blame me trying to get into a dead end here...)

If not, sorry, I don't get it. How could you standardize your relative level? I couldn't see any gasoline level unless it overflows.

The way to turn-off by the same nozzle or multiple-times turn-off_wait_turn-off are just the ways of approaching the resembling level. 3 gallons difference is too much and almost impossible by those methods of pumping. We just try to provide ways for ppl picky in calculating their own MPG info.



Anyway, so far, after 7k miles driving, I find out the trip computer of 04TL is quite accurate. If drivers could reset it each time after being the gas station, the reading is really trustable.

rljones

Yes, I was referring to the trip odometer (I don't believe it possible--it is certainly not legal--to change the main odometer).

As for standardizing, I was simply implying that for a given station, the auto turn-off settings for their pumps should be rather constant. By not topping off your tank, and instead letting the pump decide when it is done filling, you should be filling it to a 'relatively' consistent level. This in turn should lead to a better mileage figure. Even better to use the same pump when possible to further minimize errors. Keep in mind that with the values we're talking about, a 0.5 gal error will roughly affect the mileage calculation around 1 MPG for a 13 gal fill-up. (I wouldn't get too caught up in precision.)

Once you start topping off your tank, you can never be exactly certain how much you've topped (ie, when to stop topping). I'd just let the auto turn-off be the end point of fill-up if I want to calculate my mileage--and you need to do this at least twice and calculate on the 2nd tankful since the 1st tankful may be misleading due to toppping.

rets

rljones,

Thanks for your reply. I see your points now. We are absolutely talking about the same thing, auto shut-off/turn-off feature is identical as the term "top-off" I used above. When bubbles/gasoline/vapor reaches the nozzle, the turn-off takes place, that's the point equal to the top level at that time.

In order to make less confusion, I made changes.

Ron A

I have been stopping at the first shutoff of the nozzle, and not topping off (as many of you stated in this thread) for many, many years, but I always start out with a couple of testing procedures. Each time I get a new car, I fill it up completely, no matter how long it takes. This tells me how much empty space remains after the first shutoff of the nozzle.

Now that I know this, I am ready for my next step. I will run the tank almost empty. When I feel the first hesitation due to low fuel, I will stop and put 1 gallon of gas from a gas can in my trunk, and then proceed to the nearest gas station. Then, I will fill the tank to the very top again, accounting for the 1 gallon of gas I put in and the distance to the gas station.

Since the tank was completely empty, this will give me lots of information, because I will have noted the MID miles to empty when the low fuel warning light came on, and the miles driven to empty after the light came on. I will report my findings when this phase has been completed.

If you have read this far, let me assure all of the concerned folks here (which I appreciate), that when this test is done, I will not top off and will also not allow the tank to become empty (or even near-empty) again.

All of this will either confirm or deny my opinion that, based on my first fill-up, there is no reserve, and when the MID says zero miles to empty, there is virtually no fuel remaining in the tank, and when the low fuel warning light comes on there is approximately 1 ½ gallons left in the tank.

I know this probably seems weird to a lot of you good people, but I just like to know what is going on when my car tells me something because I hate to run out of gas especially if it is dark, raining, no gas station in sight, and I don’t own a cell phone.

rets

Ron A,


I still believe Low Fuel Indicator Light and Miles to Empty are just the two-step early-warning system for 04TLers. Comments about too-early or too-late are just all about the personal preference.

Nevertheless, if you're interested in testing your tank's limit, we're glad to know your result and would appreciate your efforts. Please. Mabye you can also let us know how many gallons difference will be between the nozzle's auto-shut-off and tank's top-off.

I wish I could find the used tank out of the junkyard and test it.

greenseed

I've reset my trip computer just before going on a short 75 mile highway trip and I average about 33mpg. Of course this average drops once hitting secondary roads but I was amazed with that MPG in a car that only was showing about 600 miles on the clock.

Overall my commuting MPG average has risen from 23MPG to 25MPG. I'm now up to 2200miles.

mcm244

With regards to the accuracy of the fuel gauge, many on this forum seem to interpret this as a quality problem. IMHO, I believe Acura/Honda planned this from the get go. No only with the TL, but with all their vehicles.

Before my TL, I had a '95 Integra. One night, I was heading PA-323W back to Penn State with about 1/4 tank according to my gauge. I figured I would just find a station along the way and fill her up. But, every gas station I passed was closed. Then, the "empty" light came on. Luckily, I found a gas station that was soon after that. Although the fuel capacity was 13 gallons, I was only able to put a little more than 10 gallons in the tank.

I personally don't see this as a quality problem or issue. Yes, it may not be accurate. But, this appears to be Acura's way of keeping us out of trouble. In fact, I wouldn't be surprised if the speedometer reading was slightly higher than the actual speed.

Mark

Ron A

Not to beat a dead horse to death, but I feel the need to make a comment here after reading every thread in this forum on fuel capacity, miles to empty reading, and low fuel warning light.

As I stated in my first posting to this thread, my MID showed miles to empty 10, and the low fuel warning light had been on for about 45 miles when I filled up.

The nozzle shut off at 14 gallons. When everyone else says this, they assume there is 3 gallons left in the tank. But, after it shut off at 14 gallons, I put an additional 2.8 gallons into the tank, for a total of 16.8 gallons. This has to mean that I was running on fumes and only had .2 or .3 gallons left, at the most.

I believe the tank was designed this way to allow for expansion and reduce emissions. My 1987 Olds 98, which I still have, is the same way. The owner's manual says it is an 18 gallon tank, but I got 21 gallons in it the first time I tested it, and then went back to the normal method of quitting at the first nozzle shutoff.

I will be performing my second test soon by letting the tank empty (first hesitation, not running until completely dry), and then filling completely to the top to check exact fuel capacity. Then I will know for sure if my theory is correct about NOT having 3 gallons left after the first nozzle shutoff.

rets

Ron A,

I got no idea how car makers measure the capacity of fuel tank. If 04TL has 17 gallons space, does this mean that is the full volume of the tank or just the ~85% of the tank (not including the fueling pipe from the left side to the tank)? Or perhaps your previous gas station's fuel or nozzle had generated too much bubble or fume when filling up. I never overflow the gasoline yet, so have no idea how deep our tank is.

As mcm244 said, I got the similar experience in PA, too, that's the night I skipped the first exit and gas station (Low fuel warning light was ON for a while) and spent next hour to exit and find another qualify gas station. When finally getting one, it's at "Miles to Empty = 0" for a long time. The nozzle shut-off was almost 16 gallons, and tried two more shut-offs, I got total 16.3 gallons... this is the experience I don't want to have again.

I'm interested in the final fact that how many gallons you could put into your 04TL after some extremely extended drive. IMO, we're talking about what we have in the tank after the Low Feul Warning light is ON, right? You just want to make sure if there is really 3-5 gallon left in the tank or only 1-2 gallon left with lots of fumes inside.

Thanks for taking this test.

Mine Low Fuel Warning light is ON now, I'll try to fill up and post the final numbers here tonight.

rets

I changed my mind and went to fill up my tank a moment ago.

Here is all the data & parameters.

Low Fuel Warning light is ON

AVG MPG 17
AVG MPH 19

MILES TO EMPTY: 29 MILES

EXXON 93@$2.059

1st auto-shut-off: 12.956 gl.

10 seconds later,
2nd auto-shut-off: additional 0.137 gl, total 13.093 gl.

10 seconds later,
3rd auto-shut-off: additional 0.134 gl, total 13.227 gl.


Try to fill it up slowly until it overflows: additional 0.842, total 14.069 gl.

IMO, so at this point, btwn Low Fuel Warning and MILES TO EMPTY=0, theoretically, there is (17-14.069)=2.931 gl left in my tank. (The nozzle at least auto-shut-off 20 times during this process, I had to remove it a little bit and force it to keep filling up to the limit.)





My Trip Computer Infomation displayed before/after I filled up the gasoline.

##ITEM, before, after##
Sampled FL,
1.7 gal, 16.1 gal

Measured RF,
1.7 gal, 16.1 gal

Refuel FL,
2.1 gal, 16.1 gal

Calculated RF,
1.7 gal, 16.1 gal

RAFE,
15.3 mpg, 15.0 mpg

Display Range,
7.5 miles, 237.5 miles

Calculated Range,
27.3 miles, 257.3 miles


TO Ron A, I really like to know how you put 16.8 gallons into your car... :wow:

Ron A

To rets: Very very slowly, but I did. Should run out of fuel sometime tomorrow and will do the empty tank test and report again.

So far: Your way-approx 3 gl left in tank
My way-almost nothing left in tank
Will know more tomorrow

rets

Anyone knows what is the meaning of 17 gallon capacity at 04TL?

Does it mean the complete space of the tank, from the bottom to the fuel mouth of the left side of the car?

Or this 17 gallon is just a big portion of the tank without the tube from the tank to the mouth?

Thanks.

Chitown-TL

Just curious but why do you want to know? What difference does it make?

Ron A

Finally got my tank empty. Thought it would never get empty, but it finally did. Here are my findings.

Orange low fuel warning light comes on when miles to empty: 37

Set trip meter B to 0 at this point. Miles on trip meter B when I ran out of fuel: 57

Total miles driven after orange low fuel warning light came on: 94

Conclusion: You can go a long ways after the low fuel warning light comes on.

Filled tank completely. Here are the findings for this. Of course, this part has nothing to do with the above furnished information and is a completely different topic, but I just wanted to know everything there is to know about this.

First nozzle shut off: 16.3 gl Remember, it was completely empty. If there was about 2 ½ gallons left, which is what I figure was in there if you filled up when miles to empty said zero, this would have given me a first shut off of approximately 14 gallons, which is what others have been reporting here and is absolutely normal.

Kept going and filled tank to brim. The conclusion: an astonishing 19.5 gallons, which means there is an expansion and emissions factor involved in having a larger capacity than rated.

Total miles driven on tank 494, put in 19.5 gallons (tank was also completely full at last fill up so this computation is accurate), average mpg 25.3. Pretty good considering about half in town traffic and the other half between towns (not interstate or highway driving).

FINAL CONCLUSION: I will NEVER do this again. I will NEVER put more fuel in the tank after the first nozzle shutoff. I will NEVER run the tank anywhere near empty. I WILL put fuel in shortly after the low fuel warning light comes on, meaning I will still have about 3 gallons left in the tank so the pump doesn’t run dry and the sediment won’t come up and the condensation will be kept at a minimum.

Thanks for listening, and I hope this helps you folks who are interested in this type of stuff. If you have to ask why you would want to know this, then you are not interested and can stop reading here.

rets

Just try to end the debate in the future... ppl will keep asking fuel tank capacity issue... IMO...

rets

Seems like we're the only two guys interested in this...

So, in the beginning of the test, was your tank full, about 19.5 gallons? (I saw your 2/19 post saying it's full) I have to figure out this. If your original tank in the beginning was not full, your data makes sense. If this was full, your data is a little weird.


Do you mean it's 37 miles between low fuel warning and Miles to Empty? Then, beyond Miles to Empty, you can run 57 miles more until it's really empty.

If so, this 94 miles divides by your aver mpg 25.3 = 3.715 gallon. And, this just means you have approximately 3.715 gallon after the Low Fuel Warnig light is ON. And, this is almost identical to my regular fueling. I run to Low Fuel Warning point and fill up the tank, it's about 3.773 gallons left.

So, the really full tank of 19.5 gallons should drive more than 494 miles you have tested, which also means your test-tank didn't fill up as we thought "full".



IMO, 19.5-gallons number seems the limit of our tank in 04TL. (17 gallons of full tank + 2.5 gallons in reserved tank)

Low Fuel Warning Light ON is about 4 gallons left + 2.5 gallons in reserved tank.

Miles to Empty=0 is about... I couldn't analyze this data. It's not right...

If you're not using 19.5 gallons to run this test, this data will possibly make sense.

brusie

I wish acura would just tell us the truth about our tanks, so we don't have to go through all this. It doesn't bother me that my car says its empty and only fills up 13 gallons, but I don't understand why they can't tell us exactly how many gallons are left when MTE goes to 0, or when the low fuel comes on.

Ron A

Rets
1. Yes, the tank was full to the brim at the beginning of this test. Remember, I said I put in 16.818 gallons, and at that time I thought the tank was almost empty because the miles to empty was 10, but now I know I must have had just under 3 gallons left in the tank, but it was full to overflowing at that time.
2. Yes, 37 miles between low fuel warning and miles to empty zero, then another 57 miles until the tank ran dry.
3. With a really full tank to a really full tank, and going 494 miles, my average miles per gallon was 25.3, which is just about right for the kind of driving I was doing, and also agreed with the trip computer,
4. There is no “reserve tank”, as such. You can call it that, but it is really a matter of the low fuel warning light and the miles to empty gage being very much on the cautious side.
5. The figures are all correct and all make good sense.
a. 19.5 gallon actual capacity, approximately 17 gallons everyday, real world capacity and the figure you can use when computing how many miles you can get to a tank because that is about what you will have in the tank if you stop at the first nozzle shutoff.
b. 494 miles on a FULL 19.5 gallon fill-up gave 25.3 mpg, which is a realistic figure for the type of driving I was doing.

So, bottom line:
a. If you stop at the first shutoff, you will have about 17 gallons in the tank.
b. When the low fuel warning light comes on, you still have about 3.71 gallons left in the tank (94 miles divided by 25.3 mpg)
c. When miles to empty reads zero, that is time to fill up, but you still have about 2 gallons left in the tank (57 miles divided by 25.3 mpg)

THE END!

rets

Bingo... the great note to end the thread.

Thanks. Ron A.

Car is still ok?

Formula 350

Thanks for all the info.

As someone asked earlier about the 17 gal capacity...

It is the TANK and does not include any of the tubing. Most cars can get an extra gallon or so in the fill tube if you try.

Ron A.. I hope you did not 'fill up' your emission resevoir. There is supposed to be a place for the fumes to go and I have heard of someone with a different car filling it up when topping up like you did. That is why they keep telling people NOT to top up the tank. If you fill it up then the emissions go up.

I also agree with your post about 'reserve tank' There is no such think except on some pickup trucks which have two tanks. It is a reserve amount.

But I do wish the computer was a BIT closer to being real when it says zero. Three or so gallons is a lot and the computer should be able to tell. Try filling the tank half full and it will not say you have a long way to go till empty as it knows you only have half a tank.

Ron A

rets-my car is still doing great. I have a 20XXX VIN and so far have not experienced any of the problems I have seen reported here, except the tires and the vibration. The tires don’t bother me that much here in Florida so I will just wait and see what Acura is going to do. The vibration may go away, but I think it is in the transmission. I have some short (5-6 mile) stretches where I go about 60 and can feel the vibration, so I just put the SS in 4th and it goes away when the engine turns 2000-2100 rpm. Since I am not used to the SS yet, and haven’t had the car long, sometimes I forget it is in SS and wonder why my tach is going up so fast, but then I remember and shift up. I am getting better at it, though.

Formula 350-I don’t think there is an “emission reservoir” as such. There is just the additional space in the tank for the vapors to accumulate while you are filling up. I don’t know where they go after that, but I guess they just evaporate. I think the computer was designed to be on the optimistic side, so when you get to zero you will worry more about getting gas, since many owners don’t know about the 3 gallons remaining so they get fuel before it shows miles to empty zero and that keeps them out of trouble. I just like to have a little more control over my options which is why I always perform this test on any new car I get.

Formula 350

I do not know if the TL has one or not. However, I read on the RX-8 forum (I believe) that someone did the top up till it was at the top of the tube and the car did not run well. When they took it in they told them it was due to this resevoir getting filled with gas.

If we do not have one.... so much the better!!

Ron A

I hope that the TL is not like the RX8. So far it is still running great with about 200 miles on it since the last complete fill-up. The manual says: "Do not try to top off the tank. Leave some room for the fuel to expand with temperature changes". I think this is the real reason for not filling completely to the top. I would think that if there was another reason not to fill completely, like the RX8, that Acura would have said so in the manual. I wonder if the RX8 manual says that.

TLXLR8S

this the reason why it says empty before its realy empty.
clicl on the link
http://auto.howstuffworks.com/fuel-gauge.htm

rets

This is a good link.


However, no matter how we try to explain why Acura/car makers design this "low fuel warning" light and "Miles to Empty", some of ppl still hate this is not accurate. They need something telling them how many gallons are exactly left in their tank.

No early warning or double warning, just a plain indicator in the low fuel situation. When it's on, it only means you have to find your gas station in next gallon-like time. :wow: