Fuel Economy

[Chester_Lampwick]

Sorry to be a killjoy, but I don't believe you can calculate with any real accuracy for that small of a sample. Sure, the odometer may be that accurate, but how do you measure fuel? Certainly one pump could click off sooner when fueling. That could make a difference of a couple litres.

Typically, you'd want to calculate over three or more tankfulls. This would cancell out pump differences, but would give you a combined fuel economy / consumption.

Just pulled off 7.6L/100 km (pump measured), 98km trip all highway, done as part of an out of town trip and as an experiment.

2010 MS3

pluses:
- drove between 100 and 105, sometimes 110
- cruise off, fan off, radio on
- no sudden accel or boost
- SRI possibly improves air intake efficiency
- did not drive behind anyone for much of the trip so slipstreaming is not a factor

minuses:
- winter gas
- minus 11 C
- winter tires
- RA mudflaps create drag
- driving soooo slowly

Interesting experiment but hardly scientific. Still pleased with the result.

[Elusivellama]

I understand what you're saying, however I have achieved this mpg or better last summer (30 - 35mpg) on about 4 - 5 separate occasions. This is the first time I have gotten it in winter temps. with winter tires. Granted the times I've achieved anywhere north of 30mpg were when I was in experiment mode.

As I've said, it's hardly scientific, but it still pleases me to see that the car can get 'good' highway mpg which is better than the EPA rating. It just requires ideal traffic conditions, road conditions and driving habits. Believe me... I will be repeating this experiment several times throughout the year, and based on what I saw last summer I expect that I should be able to pull it off consistently.

At the same time, I don't want to make it seem like I bought the car for fuel efficiency and frugal driving... I mean to enjoy the speed3 when I can and F- the fuel economy. I just like to know if I *can* get equal to or better than the fuel economy rating when I want to.

Sorry to be a killjoy, but I don't believe you can calculate with any real accuracy for that small of a sample. Sure, the odometer may be that accurate, but how do you measure fuel? Certainly one pump could click off sooner when fueling. That could make a difference of a couple litres.

Typically, you'd want to calculate over three or more tankfulls. This would cancell out pump differences, but would give you a combined fuel economy / consumption.

[DaveIrwin24]

Just got my ms3 a week ago, first tank got about 480km out of it, highway/city. Mind you I was punching the gas more then normal. Half way thru my second tank now, got about 230km out of it. Driving it easier. Car is says 11.8L/100KM. Will it get lower the more I drive?
Wife has a 2011 Chevy cruze, when she first started driving it, gas mileage was 10.9 and gradually went down after a month

[zzz3]

i'm averaging about 28mpg in winter mode (70/30-hwy/cty)
+always in 5th or highest gear
+i avoid downshifting
+stay in the right lane (bonus points for drafting)

I could do slightly better if i didn't:
-occasionally downshift so i can hear the exhaust 'roar' (racing beat is dead quiet when cruising)
-fooling around in triptronic so i can hear cai and pretend i drive manual

hoping to avg 30mpg consistently this summer with lighter rims (had rx8=21lbs; 42lbs total with tire )

[v_v]

hm, 7.6 ... 9.0 ... 10.9 ....
I have M3 GT and 99% city driving and as a result - 12.9L/100, but i guess it could be worse )))

[MM3 Sport]

my 2010 Sport GX 2L gets 6.4 - 7.2 L/100km on 401 rush hour traffic even in winter. keep revs below 3000 rpm around 100kph, anticipate and coast in neutral as much as possible. install air scoop ram under right "hidden nostril" to ram air into the intake.

[Kingshead8]

My 2007 GT HB use to do 13.0L/100KM back when I bought it, then through carefull driving got it down to 10.5L/100KM.

[Elusivellama]

my 2010 Sport GX 2L gets 6.4 - 7.2 L/100km on 401 rush hour traffic even in winter. keep revs below 3000 rpm around 100kph, anticipate and coast in neutral as much as possible. install air scoop ram under right "hidden nostril" to ram air into the intake.

Don't coast in neutral, you have no power to make sudden maneuvers, and your fuel injectors are still firing to keep the engine turning over. Coasting in gear uses the car's momentum to keep the engine turning over, and no fuel is used. If your car is a manual, the disadvantage of this method is that it puts more wear on your clutch. Not sure about automatics. Regardless, coasting in neutral is still dangerous.

[Booter22]

Don't coast in neutral, you have no power to make sudden maneuvers, and your fuel injectors are still firing to keep the engine turning over. Coasting in gear uses the car's momentum to keep the engine turning over, and no fuel is used. If your car is a manual, the disadvantage of this method is that it puts more wear on your clutch. Not sure about automatics. Regardless, coasting in neutral is still dangerous.

not to mention i remember reading at one point apart from the wear this puts on the transmission it has been know in the 6 speeds to cause noise and difficult shifting. i do believe they had a TSB noted for this as that was the direct cause of it.

[theo575]

i honestly had no clue about that neutral coasting fact thanks!

I have a 2006 GT Sdn get about 9.5L/100km in the summer, now getting 10.2L/100km, but just put a Simota SRI in so we will see what happens.

[olgeezer1]

'06 2.3GT 5spd.- 7.5 ltr/100k. at a steady 110kph.(problem here is gearing- 3000rpm at 110 is too high, but not much you can do). Around town, though probably 70% expressway, about 9.5 ltr./100k.

[Kessly Snipes]

Don't coast in neutral, you have no power to make sudden maneuvers, and your fuel injectors are still firing to keep the engine turning over. Coasting in gear uses the car's momentum to keep the engine turning over, and no fuel is used. If your car is a manual, the disadvantage of this method is that it puts more wear on your clutch. Not sure about automatics. Regardless, coasting in neutral is still dangerous.

I have a habit of putting to clutch in, while still in gear while going down hills, or to just slow down. Should I not be doing this?

[Elusivellama]

I have a habit of putting to clutch in, while still in gear while going down hills, or to just slow down. Should I not be doing this?

So you're in gear, but you push the clutch in? I think you shouldn't be doing this. The car should be in gear and clutch out when going downhill. Aside from causing the fuel injectors to shut off and/or putting more wear on your clutch (as booter pointed out) it's just safer in case you need to swerve and apply some power to avoid hitting something. Whether you're in 3rd or 4th depends on whether your engine is about to lug or not (I find lugging starts around 2300 and below on my 2.3L).

It's more of a safety issue at this point.

[Impressive]

I have a habit of putting to clutch in, while still in gear while going down hills, or to just slow down. Should I not be doing this?

Elusivellama got most of the points down, but I'd also add...

Clutching in while going down a hill in gear will also essentially remove you from the gear, causing your car to speed up as it gains momentum down the hill. Keeping your car in gear with your foot off the clutch rolling down the hill on the other end will use the gear as a brake to keep you at whatever speed you happened to be cruising at.

Great for whenever you think there will be cops at the bottom of any hill

[Prokicker]

Got my Sky last month (automatic).
Full tank upon delivery.
Fill up Feb. 20 = 10.1 L/100 km
Fill up March 13 = 10.3 L/100 km
Got less than 1400 km on the clock.
I drive mostly city, but some highway - with a little traffic.
Don't drive fast (no kick-down or hard stops).

I find that this is NOT fuel economy at all!

I've been told by the dealership that it might take a few thousand km to get to what they advertise. Called Mazda Canada to ask. They told me to keep a log of my fill ups and go back to my dealer with the info in about 3-5 fill ups.

Any thought? Opinions? Suggestions? Similar experiences?

I am very frustrated with this - although I must admit, I loooooooooove this car!

Thanks.

[Chester_Lampwick]

Got my Sky last month (automatic).
Full tank upon delivery.
Fill up Feb. 20 = 10.1 L/100 km
Fill up March 13 = 10.3 L/100 km
Got less than 1400 km on the clock.
I drive mostly city, but some highway - with a little traffic.
Don't drive fast (no kick-down or hard stops).

I find that this is NOT fuel economy at all!

I've been told by the dealership that it might take a few thousand km to get to what they advertise. Called Mazda Canada to ask. They told me to keep a log of my fill ups and go back to my dealer with the info in about 3-5 fill ups.

Any thought? Opinions? Suggestions? Similar experiences?

I am very frustrated with this - although I must admit, I loooooooooove this car!

Thanks.

You are not doing the calculations right. You can't start calculations from the delivery of the vehicle on a "full" tank. I'm sure you could fill it until the pump clicks the first time, then drive 100kms and still have the gauge read full. Or perhaps they filled it with 40 litres because they know they can short fill and still appear like they gave you a full tank. That's different then you pumping until it clicks, then trying to get another couple litres in.

Start with something like this:

Fill # ODO Kms Litres pumped Litres used Kms travelled Notes
1 300 40(disregard) 0 0 This is your starting ODO
2 700 41 41 400
3 1130 37 78 830
4 1550 38 116 1250 This is your end ODO


The formula (litres used / kms travelled)*100 = fuel consumption

(116/1250)*100 = 9.28 litres/100kms.

Notice I didn't assume it took me 40l to go 300kms that you see on line one? The first fill-up must be one you do(your style and choice of pump) and you must only record the odometer. Notice that I averaged three fill-ups to reduce error due to pump shutoff differences?

If I did:

Fill # ODO Kms Litres pumped Litres used Kms travelled Notes
1 300 40 40 300 13.33 l/100km
2 700 41 41 400 10.25 l/100km
3 1130 37 37 430 8.6 l/100km
4 1550 38 38 420 9.0 l/100km


Notice how the first couple of results look terrible? That's because I used the right numbers in the wrong manner.

[Astig02]

Got my Sky last month (automatic).
Full tank upon delivery.
Fill up Feb. 20 = 10.1 L/100 km
Fill up March 13 = 10.3 L/100 km
Got less than 1400 km on the clock.
I drive mostly city, but some highway - with a little traffic.
Don't drive fast (no kick-down or hard stops).

I find that this is NOT fuel economy at all!

I've been told by the dealership that it might take a few thousand km to get to what they advertise. Called Mazda Canada to ask. They told me to keep a log of my fill ups and go back to my dealer with the info in about 3-5 fill ups.

Any thought? Opinions? Suggestions? Similar experiences?

I am very frustrated with this - although I must admit, I loooooooooove this car!

Thanks.

It is still in the break-in period. It is gonna get better soon.
mine is a 11 Gt 2.5 and used to complain on bad fuel economy.
but with warmer weather and getting used to the driving dynamics, fuelled economy started to improve. With 100% city driving, I mow get 9-10l/100km. Used to get 13-14)/100km.

So far I have almost 7000km on the car, im not sure if it is still breaking in, but the numbers looks promising to me. Off course, it is dependent in do many factors. Driving dynamics is probably the most influencial . Just my 2cents.

[thehawk]

I must have been luck this entire time. Been averaging 10L/100km since purchase on my '10 GT 2.5.

[Prokicker]

Wow! You a mathematician or am I just a dumb blonde? You completely lost me.
And I leave my iPhone to do the work.
But for the sake of the discussion...
Here are my numbers:
(Lets skip the first dealer fill up)
125 km (odo) + 49.24 L = 611 km (odo)
611 km (odo) + 51.62 L = 1113 km (odo)

So, lets only use the last entry.
1113 km - 611 km = 502 km traveled
So if I use 51.62 L to travel 502 km, it means that I need 10.3 L to travel 100 km.
Am I not doing this right?

[Prokicker]

But it's a SKYACTIV.
I am aware that you should add about 20 % to what they advertise but 7.1 to 10.3?
This is a HUGE difference!
And why is it that others (who I am sure don't drive like a grandma, like I do!) get that or around 8?

I am really trying to just enjoy this car, but I can't get passed this...

It is still in the break-in period. It is gonna get better soon.
mine is a 11 Gt 2.5 and used to complain on bad fuel economy.
but with warmer weather and getting used to the driving dynamics, fuelled economy started to improve. With 100% city driving, I mow get 9-10l/100km. Used to get 13-14)/100km.

So far I have almost 7000km on the car, im not sure if it is still breaking in, but the numbers looks promising to me. Off course, it is dependent in do many factors. Driving dynamics is probably the most influencial . Just my 2cents.

[Prokicker]

You are not doing the calculations right. You can't start calculations from the delivery of the vehicle on a "full" tank. I'm sure you could fill it until the pump clicks the first time, then drive 100kms and still have the gauge read full. Or perhaps they filled it with 40 litres because they know they can short fill and still appear like they gave you a full tank. That's different then you pumping until it clicks, then trying to get another couple litres in.

Start with something like this:

Fill # ODO Kms Litres pumped Litres used Kms travelled Notes
1 300 40(disregard) 0 0 This is your starting ODO
2 700 41 41 400
3 1130 37 78 830
4 1550 38 116 1250 This is your end ODO


The formula (litres used / kms travelled)*100 = fuel consumption

(116/1250)*100 = 9.28 litres/100kms.

Notice I didn't assume it took me 40l to go 300kms that you see on line one? The first fill-up must be one you do(your style and choice of pump) and you must only record the odometer. Notice that I averaged three fill-ups to reduce error due to pump shutoff differences?

If I did:

Fill # ODO Kms Litres pumped Litres used Kms travelled Notes
1 300 40 40 300 13.33 l/100km
2 700 41 41 400 10.25 l/100km
3 1130 37 37 430 8.6 l/100km
4 1550 38 38 420 9.0 l/100km


Notice how the first couple of results look terrible? That's because I used the right numbers in the wrong manner.

Wow! You a mathematician or am I just a dumb blonde? You completely lost me.
And I leave my iPhone to do the work.
But for the sake of the discussion...
Here are my numbers:
(Lets skip the first dealer fill up)
125 km (odo) + 49.24 L = 611 km (odo)
611 km (odo) + 51.62 L = 1113 km (odo)

So, lets only use the last entry.
1113 km - 611 km = 502 km traveled
So if I use 51.62 L to travel 502 km, it means that I need 10.3 L to travel 100 km.
Am I not doing this right?

[Kessly Snipes]

But it's a SKYACTIV.
I am aware that you should add about 20 % to what they advertise but 7.1 to 10.3?
This is a HUGE difference!
And why is it that others (who I am sure don't drive like a grandma, like I do!) get that or around 8?

I am really trying to just enjoy this car, but I can't get passed this...

If you are doing mostly city, you will get much worse mileage.

start using Fuelly.com, it will keep track of everything for you.

This is what mine looks like after just over 5000KM

[Chester_Lampwick]

Wait what? How are you getting 50 litres in on a fill up? My GS has a 50 litres tank, and I get 37 to 42 in from around 1/4 or less. Do you wait for the light to come on then drive 50 kms more? I think I get about 450 kms between fills. You should still try a couple more samples to average out any vagueries of the pump.

You might want to check the accuracy of the pump. Perhaps the station is scamming you? I still can't ever see pumping 51 litres. That's weird IMO.

[sarujo]

It's a 55L tank.

Wait what? How are you getting 50 litres in on a fill up? My GS has a 50 litres tank, and I get 37 to 42 in from around 1/4 or less. Do you wait for the light to come on then drive 50 kms more? I think I get about 450 kms between fills. You should still try a couple more samples to average out any vagueries of the pump.

You might want to check the accuracy of the pump. Perhaps the station is scamming you? I still can't ever see pumping 51 litres. That's weird IMO.

[Hoodzy]

Has anyone ever gotten 6.7L/100km strictly highway on a 2.3L?