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PNR888
21-10-2009, 11:05 PM
Hi all,

It was to my amusement to find out that I could actually pump in 67L of petrol (1 click only) in to my 65L CU2 fuel tank while the trip computer display 20 km to empty prior fill-up. This happened this evening at my local woolworth/caltex servo Voltex Ron95 petrol.
I would normally get 800-900 km per tank.

A month ago I pumped in 64.2L in while the computer trip indicate 8km left, according to the 65L capacity theory, I would only have 0.8L of juice left. (this was at another woolworth/caltex servo)

but after pumping 67Litre in tonight, that made me wonder the accuracy of those pump. and "Are we really get the amount of petrol that we are paying for?"

Or does CU2's fuel tank have this "secret chamber" that holds more fuel than its official 65L capacity?

In both occasion, the weather was not hot at all, quite cool actually. so the vaporisation should be very minimal.

Your experience and thoughts are appreciated. :thumbsup:

curtis265
21-10-2009, 11:07 PM
I don' tthink so.......

Rudy
22-10-2009, 01:00 AM
That happened to me at a 7 11 once, i filled 76L in a 70 tank. Crooks. Im concerned you said caltex as i go there now. Used to go shell , which has 'independently volume tested' on the tanks and always gave me the best mpg, but now im on 95RON and they dont have that at my shell, cant go there anymore. If your shell has 95 i would go there.

hotdc2
22-10-2009, 01:20 AM
I've always wondered this too. Many times i've noticed the $$ going up on the machine before I can hear the juice being pumped into my car. Dodgey as. Someone call A Current Affair lol

buddah51au
22-10-2009, 05:59 AM
If the fuel tank is 65 Litre capacity you could add a few liters for the filler neck if you fill it to the top. The most I have used to fill my CU2 was just under 63L, with trip computer reading 83 km till empty. I suspect the true capacity including filler neck is closer to 70 liters.

tony1234
22-10-2009, 06:06 AM
Problem is we'll never really know.Oil companies are shady as.:thumbdwn:

chrome
22-10-2009, 06:14 AM
I have a Scangauge II (fuel consumption meter) running off the OBD2 port of my Accord. The fuel usage is calculated from the ECU injector pulsing, which makes it highly accurate and is widely used by hypermiling groups.

One feature it has, is when you go to a station and fill up, it tells you the expected volume of fuel to top the tank up to full, based on what it has calculated. After filling till the nozzle clicks, I then set the ACTUAL volume into the SGII and adjust the % error. So after a few tanks, the trend normalises, and the expected % error of my car is around 1.5-2% (very acceptable).

I once went to a Shell fuel station that made that error jump to >10%! It meant the pump indicated a lot more fuel needed for topping up to full as compared to what the SGII expected. I thought it was a glitch, and ignored it. A few weeks later, I came back to this same station, and the error jumped again to >10%. The conclusion I drew from that experience was that the pump at the Shell station, was not calibrated right.

I later found out from a colleague that the same station had gotten into trouble in past times for dodgy pump calibration. It is a hit and miss affair, so I never assume all pumps are correctly calibrated.

nickxau
22-10-2009, 06:40 AM
Would it be legal/allowed to byo measuring container and just measure the pump output yourself?

Mr_will
22-10-2009, 07:28 AM
Would it be legal/allowed to byo measuring container and just measure the pump output yourself?

as long as the container meets australian standards and is <20L you can fill it at a service station.

i dont have any experience with shell, but I use to work for another brand of service station, and I know we regularly had the pumps calibrated.

I think it's unlikely that servos are doing anything shady, for the simple reason that the fines would be astronomical, and the service stations actually only make a few cents per litre on your fuel - their profit comes from the goods you buy in store.

89superstage
22-10-2009, 10:15 AM
Hi all,
My first post on OzHonda.
I have'nt had my CU2 for long but, I've had this experience as well.
Fuel filler clicked,this morning, after dispensing 64.4L, but the Trip said, I had 40km till empty. @10.9L/100k....
I'll try the Shell across the street next time and see how much go's in.

Did notice though that the tank had filled almost all the way up to the brim, without me trying to squeeze more in.

chrome
22-10-2009, 11:12 AM
as long as the container meets australian standards and is <20L you can fill it at a service station.

i dont have any experience with shell, but I use to work for another brand of service station, and I know we regularly had the pumps calibrated.

I think it's unlikely that servos are doing anything shady, for the simple reason that the fines would be astronomical, and the service stations actually only make a few cents per litre on your fuel - their profit comes from the goods you buy in store.

If their pumps are miscalibrated to say 5% inaccuracy, it means they actually charge consumers for 105 liters for every real 100 liters sold. That's a profit of ($1.20 x 5) just from inaccurate calibration, plus the few cents per liter from the legitimate 100 liters. Depending on the volume of petrol sold every day, that could account for a fair bit of $$ profit.

buddah51au
22-10-2009, 11:36 AM
If their pumps are miscalibrated to say 5% inaccuracy, it means they actually charge consumers for 105 liters for every real 100 liters sold. That's a profit of ($1.20 x 5) just from inaccurate calibration, plus the few cents per liter from the legitimate 100 liters. Depending on the volume of petrol sold every day, that could account for a fair bit of $$ profit.

My understanding is that when pumps are calibrated the allowable tolerance is + or - 2%. Someone within the industry would know if in fact that is still the case these days.

Mr_will
22-10-2009, 12:00 PM
If their pumps are miscalibrated to say 5% inaccuracy, it means they actually charge consumers for 105 liters for every real 100 liters sold. That's a profit of ($1.20 x 5) just from inaccurate calibration, plus the few cents per liter from the legitimate 100 liters. Depending on the volume of petrol sold every day, that could account for a fair bit of $$ profit.

compared to the profit from goods sold in store it is insignificant. petrol stations simply wouldnt bother (at least the major chains) because its not worth the risk.

tony1234
22-10-2009, 04:56 PM
compared to the profit from goods sold in store it is insignificant. petrol stations simply wouldnt bother (at least the major chains) because its not worth the risk.
True.But i still don't trust them.

tknova
25-10-2009, 07:35 AM
I just filled up at Mobil in Altona.

Had 8km until tank empty, took 63L and i topped it up all the way until fuel was about to spill out of the filler neck.

PNR888
25-10-2009, 09:26 PM
I just filled up at Mobil in Altona.

Had 8km until tank empty, took 63L and i topped it up all the way until fuel was about to spill out of the filler neck.

During the ownership of my CL9, I never have to fill over 65L, came very close a few times when it was very empty. Mine was 2003 model, didn't have trip computer, so I had to go by approx km travelled after the warning light is up.

With my wife's 08 CR-V, there are a few occasions that the trip computer indicated 0 km left, but always took less than 58L (official capacity) to fill up.

yfin
26-10-2009, 08:03 PM
My understanding is that when pumps are calibrated the allowable tolerance is + or - 2%. Someone within the industry would know if in fact that is still the case these days.

I used to work in petrol stations - it is something like 0.3% accuracy tolerance. Usually pumps are dead accurate - but sometimes they can play up.

It is not that hard to test - why don't you ask the petrol station to test that pump?

i-vtec
27-10-2009, 11:38 AM
a customer of mine runs a petrol station and they all get tested for accuracy. don't know what's the tolerance range.

they are forced to change the pumps when its not accurate.
even if it pumps is filling more n they are losing a bit they are require to change their pumps also

cbol55
27-10-2009, 12:13 PM
I would be interested to know about quality and composition testing as i have noticed (could be my imagination?) that the same brand and type of fuel from different outlets give different performance/economy...assumed it must be water/additives/not the stated product

cbol55
27-10-2009, 12:15 PM
I know its a regulated industry but the rules and laws are only as good as their enforcement

Rudy
27-10-2009, 01:30 PM
I know its a regulated industry but the rules and laws are only as good as their enforcement

this, ive got ripped off before. Only go to reputable outlets now ,eg shell.

demons21
27-10-2009, 01:57 PM
I have an 06 CL9 euro, and I have the same problem, when I get fuel from my Local Shell Station.. I might start going to Mobil and see what happens..

mpricecs
28-10-2009, 09:42 AM
Thought I'd run my 09 CU Euro Luxury down to near empty (24km to empty) and fill. Took 67.09 litres!

I think this is a Euro thing, and that the nominal size of the tank is 64 litres.

I wish the trip computer could display the amount of fuel used. My previous car did and the Euro should be able as it is required to calculate avg. fuel consumption. If we knew how much fuel was used (from the trip computer) it should closely tally with the amount put in to refuel - it always did on my previous vehicle.

buddah51au
28-10-2009, 04:24 PM
That is the same as I experience with my CU2, I believe the fuel tank capacity is 65liters + approximately 5 liters for the filler neck if you fill it to the top.

curtis265
28-10-2009, 04:27 PM
does the fuel in the fuel lines count too?

buddah51au
29-10-2009, 01:16 AM
Feul tank capacity is usually the capacity of the tank itself. any additional fuel in the filler neck or fuel lines is additional.

PNR888
29-10-2009, 07:43 PM
[QUOTE=mpricecs;2530733]Thought I'd run my 09 CU Euro Luxury down to near empty (24km to empty) and fill. Took 67.09 litres!

I think this is a Euro thing, and that the nominal size of the tank is 64 litres.

QUOTE]

You got very similar figure as what I got last time. From this and Buddah's info, CU2 must have 65L + volume of Filler neck. so total capacity could be close to 70L.

buddah51au
29-10-2009, 08:20 PM
I base my thoughts on the following - the furthest I have gone on 1 tank is 972km, it took 62.89 lts to fill it & the trip computer was showing 88km till empty. my calculations on fuel consumption for that tank with supposedly 88 km left would indicate a total capacity of around 69 ltrs & a theoretical range of 1060km on 1 tank of fuel. trying to achieve that would be Dependant on having a petrol station where it would be needed. In that instant I had about 110km to the next town, so I couldn't chance running out of fuel.

cbol55
29-10-2009, 09:43 PM
this thread started off an interesting subject but is now just another fuel comsumption thread

buddah51au
29-10-2009, 10:54 PM
i thought we were trying to work out the actual fuel capacity of the CU2, what better way than to post figures that are indicated. i did not indicate fuel consumption anywhere on that posting, only distance traveled, liters to fill the tank & indicated kms remaining.

cbol55
29-10-2009, 11:02 PM
the title of the thread is fairly self explanatory ..and it was indeed the subject matter for a short time..the direction people took it was all too familiar...the actual subject is one that affects us all...do u really know what u are pumping into your car..and if you are being charged correctly...bad enough we pay by volume which is variable according to temperature....never mind how far u can go on it..although i am someone who takes an interest in fuel economy and particularly in regard to the euro...it has been a bit done to death though

cbol55
29-10-2009, 11:08 PM
wasnt having a go at you buddah..just the thread direction..enjoy your posts and attitude....wasnt having a go at anyone really ..just the way stuff goes on the internet:D

SPQR
29-10-2009, 11:15 PM
If their pumps are miscalibrated to say 5% inaccuracy, it means they actually charge consumers for 105 liters for every real 100 liters sold. That's a profit of ($1.20 x 5) just from inaccurate calibration, plus the few cents per liter from the legitimate 100 liters. Depending on the volume of petrol sold every day, that could account for a fair bit of $$ profit.

Can we use the English spelling of litres pleaseeeee.....

tron07
30-10-2009, 08:00 AM
RON98 used to be 10 cents more expensive then RON92, but now I think its like 15 cents more already.... rip off...

tony1234
30-10-2009, 07:25 PM
RON98 used to be 10 cents more expensive then RON92, but now I think its like 15 cents more already.... rip off...
That's right.I'm sick of being gouged by,govt,oil companies,councils,RTA etc.:thumbdwn::thumbdwn:

Rob_A
01-11-2009, 10:31 PM
you will always get more then just the tank capacity, with the filler neck etc.

I have a mate that works for the nmi which deals with bowsers,scales etc before they can be used in trade making sure they read accurately under a variety of conditions.

Rob