Another fuel efficiency / gas tank concern

[Silv3r]

I know there's a few threads out there touching on some of the things I am experiencing but I did not want for good feedback to get lost somewhere else.

Have a 2008.5 AUTO GT M3 Sedan. I feel like I am not getting anywhere near enough mileage from it based on factory specs/other vehicles owned & driven by me and even most users out here.

I barely get 430 KM (on a good week) of almost 90% highway driving and that is when my light has been on for 20 - 30 km and I have had a few instances when I have driven it where the indicator tells me I have 0 Kms left (and at that point I had around 430 KM). Today I got about 370 before I filled up, light was on for a bit and indicator said I had 20 kms left.

What I have also noticed and is even more of concern is that I feel as if I am not able to fill my tank to capacity. I believe the most I was ever able to fill is 46 L's and that was with the light on, 5 KMs left on the indicator and after I kept forcing gas down the fuel opening after the pump lever kicked me back a few times. After feeling it like that I still managed to get a misley 425. Normally when the light goes on I am able to fill up maybe 43-44 Ls.

I filled up today from what mentioned about and the pump kept knocking me out at 40 Ls!!!!!! I managed to shove around 41.5 Ls and that was it.
When I turned the car on the indicator showed that I have 474 KMs left (but that is never accurate). Within like 1 KM of leaving the gas station, it went down to 470 KMs left. Now get this, I am going on the highway for about 10 KMs and I notice the indicator jumped back to 474. Then, it sat there for a few mintes and then!!!! in started going up gradually (475, 476, 478, 479!!!!)

I got tired of watching it and turned on the clock. When I got home it was back at 476 but the funny thing is, I drove approx 30 km from my fill up.


So..... What gives??!?? Am I having sensor issues, fuel pump issues, or regular every day Mazda issues that I should not concern myself with. The avg fuel consumption indicator shows 10.6L/100 KM constantly where as current gas consumption jumps all over the place from 3.1 L / 100 KM to 42 L / 100 KM.

I got around 16,000 km on the car and I do drive it too hard.

Just bothers me that I had a larger heavier american car with a bigger engine and I got more mileage out of it than smaller engine / lighter Mazda.

Thanks!

*PS: Where's my avatar pic

[Malcolm991]

You should get better mileage then that! I get 530km to 570km to a tank and I have done 650km on a trip!

[Silv3r]

You should get better mileage then that! I get 530km to 570km to a tank and I have done 650km on a trip!

Alright so I'm not going crazy. Any idea why?

Anyone else care to weigh in?

I never got 500 since I purchased the vehicle!

[Noisy Crow]

Alright so I'm not going crazy. Any idea why?

Release the parking brake? :chuckle

Seriously though, check for brake drag, under-inflated tires etc. Do you have an automatic or manual?

[slam525i]

The range indicator goes up because as you drove home, the average fuel economy (not necessarily what it was showing you but what the computer uses to calculate range) increased. That plus you topped it up beyond what the sensor could read as a full tank.

The instant fuel economy reading always jumps around a lot. A very slight up hill or downhill, very slight change in throttle position, etc. etc. It's really useless unless you're on a perfectly flat road at fixed speed. You can even see it change if you're on cruise control and someone else pulls in front of you (aerodynamic drag).

The fuel indicator lies. A lot. In any car. I keep fueling my 2010 GT at 1/3 to 1/4 tank and it only lets me put in low 30's in liters. I bet it would still have 10 or so liters when it shows "empty". I'm sure if you drove it till it's empty (i.e. engine stalls out), then you can fill your tank to the rated capacity (and probably a little more).

The only "issue" with Mazda 3 fuel economy being unstable is that we're not stable in how we drive the car. Sometimes we give it some whip, sometimes we cruise on the highway. Don't worry about it and just enjoy the car. If you really want to save fuel, drive more gently. If you don't want to visit the gas station as often, just run it down more before fueling. Just don't blame me if you stall out somewhere or your fuel pump dies. :chuckle

[Silv3r]

Release the parking brake? :chuckle

Seriously though, check for brake drag, under-inflated tires etc. Do you have an automatic or manual?

No tires are fine, no brake drag that I am aware of.........not sure what that is actually haha (like my breaks being applied while I am not applying them?). Car is automatic.

[Silv3r]

The range indicator goes up because as you drove home, the average fuel economy (not necessarily what it was showing you but what the computer uses to calculate range) increased. That plus you topped it up beyond what the sensor could read as a full tank.

The instant fuel economy reading always jumps around a lot. A very slight up hill or downhill, very slight change in throttle position, etc. etc. It's really useless unless you're on a perfectly flat road at fixed speed. You can even see it change if you're on cruise control and someone else pulls in front of you (aerodynamic drag).

The fuel indicator lies. A lot. In any car. I keep fueling my 2010 GT at 1/3 to 1/4 tank and it only lets me put in low 30's in liters. I bet it would still have 10 or so liters when it shows "empty". I'm sure if you drove it till it's empty (i.e. engine stalls out), then you can fill your tank to the rated capacity (and probably a little more).

The only "issue" with Mazda 3 fuel economy being unstable is that we're not stable in how we drive the car. Sometimes we give it some whip, sometimes we cruise on the highway. Don't worry about it and just enjoy the car. If you really want to save fuel, drive more gently. If you don't want to visit the gas station as often, just run it down more before fueling. Just don't blame me if you stall out somewhere or your fuel pump dies. :chuckle

A lot of valid points that I have considered also but at the end of the day, I want a car that on average gives me more than 460 kms at least on an average tank filled up to 45/46 liters (which I can not even seem to fill up that much). Tell me how much you get out of your 2010 GT from a fairly full tank fill up regardless of how you drive and then we can discuss further.
I do enjoy the car but now I have to fill up 2 to 3 days sooner than I used to with my older car it seems.

[slam525i]

I'd love to tell you how much I get, but I've never run the tank down that much, and really, i don't plan to. Mathematically, I would get 615 km (9.75L/100 km; 60 liters) but this was all break-in mileage with almost no highway and a lot of keeping the revs up. I will know better after this tank since I'm done the break-in period, although I don't drive to work/school so I really don't know how much of my driving is on highway.

A little side note, I was taught to never, ever trust the fuel gauge in airplanes. Fuel up, and then calculate based on a pessimistic fuel consumption and decide how far you can really go safely. I apply the same thing to cars. You can do the same thing.

Reset your average fuel consumption when you fuel the tank up, and reverse calculate how much fuel you should have in your tank as you drive. Fuel up when you calculate you have 10 liters left. That should give you plenty of margin.

Just don't run it too much lower than that. Bad for the fuel pump.

[Silv3r]

I'd love to tell you how much I get, but I've never run the tank down that much, and really, i don't plan to. Mathematically, I would get 615 km (9.75L/100 km; 60 liters) but this was all break-in mileage with almost no highway and a lot of keeping the revs up. I will know better after this tank since I'm done the break-in period, although I don't drive to work/school so I really don't know how much of my driving is on highway.

A little side note, I was taught to never, ever trust the fuel gauge in airplanes. Fuel up, and then calculate based on a pessimistic fuel consumption and decide how far you can really go safely. I apply the same thing to cars. You can do the same thing.

Reset your average fuel consumption when you fuel the tank up, and reverse calculate how much fuel you should have in your tank as you drive. Fuel up when you calculate you have 10 liters left. That should give you plenty of margin.

Just don't run it too much lower than that. Bad for the fuel pump.

Believe me, I would love to always feel up at when I have a quarter or more left but I feel like I need to run it dry. When you get just under 400 (not 400 but under) and your light comes, that is quite frustrating and should not be happening. At a quarter of a tank, I probably average around 330ish. Regardless of what you mentioned, with your driving habits, when you hit approximately a quarter of a tank, do you get my numbers or no? if you get on average 400 or so at a quarter of a tank, my crazy forces of deducting make me believe that something is not quite right on my end.

[slam525i]

My first 3 fuel ups, I got
362 km from 37 liters, showing 1/3 tank before fill.
420 km from 41 liters, showing 1/4 tank before fill.
358 km from 34 liters, showing 1/3 tank before fill.
(Keep in mind the 2010 models have lights for the gauge, not a needle)

The problem is "1/4 tank" is just so meaningless a measure because it always indicates less fuel than you really have. It's so that you will fuel up early and not get stranded on the side of the road. I think everyone is getting far less than 3/4 of rated fuel capacity into their tank when they supposedly have 1/4 tank left.

Example: my tank is 60 liters. 1/4 tank should be a 45 liter fuel up and a 1/3 tank should be a 40 liter. I'm consistently getting less than that into the tank. I use to have a 525i where I could drive 30 minutes on highway with the low-fuel light on and still have 12 liters left in the tank, but the gauge was showing zero/reserve. Fuel gauges lie. Learn to ignore it.

As long as your math shows you're getting around 10L / 100 km or better, nothing's wrong with the car.

Also, you really shouldn't run your tank down too much unless you have good reason to. The fuel acts as a heat-sink for the fuel pump, and extremely low fuel levels can cause cavitation/aeration, again hurting the fuel pump. Why do you feel like you need to run it dry?

[Iceman_F1]

I know there's a few threads out there touching on some of the things I am experiencing but I did not want for good feedback to get lost somewhere else.

Have a 2008.5 AUTO GT M3 Sedan. I feel like I am not getting anywhere near enough mileage from it based on factory specs/other vehicles owned & driven by me and even most users out here.

I barely get 430 KM (on a good week) of almost 90% highway driving and that is when my light has been on for 20 - 30 km and I have had a few instances when I have driven it where the indicator tells me I have 0 Kms left (and at that point I had around 430 KM). Today I got about 370 before I filled up, light was on for a bit and indicator said I had 20 kms left.

What I have also noticed and is even more of concern is that I feel as if I am not able to fill my tank to capacity. I believe the most I was ever able to fill is 46 L's and that was with the light on, 5 KMs left on the indicator and after I kept forcing gas down the fuel opening after the pump lever kicked me back a few times. After feeling it like that I still managed to get a misley 425. Normally when the light goes on I am able to fill up maybe 43-44 Ls.

I filled up today from what mentioned about and the pump kept knocking me out at 40 Ls!!!!!! I managed to shove around 41.5 Ls and that was it.
When I turned the car on the indicator showed that I have 474 KMs left (but that is never accurate). Within like 1 KM of leaving the gas station, it went down to 470 KMs left. Now get this, I am going on the highway for about 10 KMs and I notice the indicator jumped back to 474. Then, it sat there for a few mintes and then!!!! in started going up gradually (475, 476, 478, 479!!!!)

I got tired of watching it and turned on the clock. When I got home it was back at 476 but the funny thing is, I drove approx 30 km from my fill up.


So..... What gives??!?? Am I having sensor issues, fuel pump issues, or regular every day Mazda issues that I should not concern myself with. The avg fuel consumption indicator shows 10.6L/100 KM constantly where as current gas consumption jumps all over the place from 3.1 L / 100 KM to 42 L / 100 KM.

I got around 16,000 km on the car and I do drive it too hard.

Just bothers me that I had a larger heavier american car with a bigger engine and I got more mileage out of it than smaller engine / lighter Mazda.

Thanks!

*PS: Where's my avatar pic

I'll start with the bottom concerns first. The "current gas consumption" is constantly changing because you aren't keeping a constant on the gas pedal. It's a guide to see if you are really pushing the car or letting it relax.

Your average consumption is a bit more accurate but I found the calculations sometimes as much as 1 full L/100km off. So your 10.6L/100KM might be closer to high to mid 9's instead.

The problem with the "90% highway" is that doesn't really mean too much. I do 70% highway. 40KM to work, 50KM home (different route). In the morning, it's normally avg. 100km/h on the highway. After work it's avg. 120km/h or higher to pass. Those 20km/h over the speed limit will negatively affect my mileage. Your 90% highway would depend on speed, total distance, and a bunch of other factors.

Here's a link to a HTML export of my excel gas spreadsheet to show how up and down mine is (08.5 GT Auto hatch). A note for the spreadsheet. All litre values were taken at first click of the hose. "Not a full fillup" in the notes section means I could still do at least 1 trip to and from work (90-100km) but chose to fillup either because of a good gas price or because I knew I was going to do a somewhat long trip and wanted to be sure I had gas.

Iceman_F1's Gas Mileage (http://dump.sdamv.com/Gas.html)

There are a bunch of factors though that will affect it. If it's really a concern and really bad, maybe try talking to the Mazda dealership that you go to for service and see what they might say? Either way, I noticed my "max" fillup was like 520km or so...

[KenYork]

Think about it this way. We have 55L tanks, so if your only filling up 40-44L and getting about 400kms. You still have about 10-13L in your car when the light is on which should add up to another 100kms or so.

[sunkist4338]

Think about it this way. We have 55L tanks, so if your only filling up 40-44L and getting about 400kms. You still have about 10-13L in your car when the light is on which should add up to another 100kms or so.

this makes total sense

[shu5892001]

Think about it this way. We have 55L tanks, so if your only filling up 40-44L and getting about 400kms. You still have about 10-13L in your car when the light is on which should add up to another 100kms or so.

:)

[victor_t]

another thing to consider about the average gas consumption is that we don't know how long the averaging window is. you can reset the average by holding down the "set" or "info" button. otherwise it keeps averaging over the previous data.

if you drive the car hard of course you will waste more gas.

on my car when accelerating hard the fuel consumption goes as high as 40 liters per hundred kilometers. when I'm in fifth gear doing a steady 100 to 120 km/hr I'm doing between 4.5 and 6.5 liters per hundred kilometers.

if you use cruise control the fuel consumption is lower.

if you drive slower (90 km/h instead of 120 or more) the fuel consumption goes down.

my average consumption is 8.5 liters per hundred, for a mix of city and highway traffic, not driving too aggressively (2007 2.0L manual with 42000 km and also still with winter tires)

[slam525i]

another thing to consider about the average gas consumption is that we don't know how long the averaging window is. you can reset the average by holding down the "set" or "info" button. otherwise it keeps averaging over the previous data.

I can't say for certain, but most cars simply calculate fuel consumed since reset, and distance traveled since reset, and then calculate the average fuel consumption based on that. It doesn't keep accumulating and then rolling over old data.

However, the range calculation is usually based on a different number that is determined separately based on more recent (but not instantaneous) fuel consumption. This does accumulate and roll over old data.

[DreamM3]

I get, on average 570 km/tank on 50/50 highway and city. I did 90% highway on the weekend and got to 280 km on a 1/3 tank...

You should be getting more. I don't care what people say on here. My friend has a 2008.5 hatchback 2.3L and get about 530 a tank. i know this because I had his fro a week while he was in Texas. My ex-girlfriend's mom had a 2006 2.3L hatch and she constantly got around 530 km/tank as well.

Ridiculous.

[DreamM3]

I get, on average 570 km/tank on 50/50 highway and city. I did 90% highway on the weekend and got to 280 km on a 1/3 tank...

You should be getting more. I don't care what people say on here. My friend has a 2008.5 hatchback 2.3L and get about 530 a tank. i know this because I had his fro a week while he was in Texas. My ex-girlfriend's mom had a 2006 2.3L hatch and she constantly got around 530 km/tank as well.

Ridiculous.

You can notce I was turbo typing with all my typo's :bang

[slam525i]

Okay. That's it. The next person who says "xxx km per tank" is going to get smacked :complain

What is a tank? Full fuel capacity? Fueled up to the filler neck and then run till the engine stalls out? Some people fuel up early, some people run their cars until there's only fumes left in the tank.

If we're going to make this meaningful, we have to use "liters/ 100 km".

[Iceman_F1]

Okay. That's it. The next person who says "xxx km per tank" is going to get smacked :complain

What is a tank? Full fuel capacity? Fueled up to the filler neck and then run till the engine stalls out? Some people fuel up early, some people run their cars until there's only fumes left in the tank.

If we're going to make this meaningful, we have to use "liters/ 100 km".

XD

Yeah, so true. My "max" was 513km in a single tank. That was filled up for a total of 44.444 litres for a 8.66L/100km rating. I usually avoid saying "xxx km per tank" because you're right, everyone fills up differently. I will say that my avg. is about 9.2L/100km. Do I wish it was better? Of course...but it's not terrible either.

[insaini]

filled up 2 days ago ... got around 400 km on 3/4 of a tank

07 mazda 3 hatch 2.3 L

[Malcolm991]

I filled up today when my light turned on! I got 548km from that tank with 40km left! It took 46 ltrs to fill!

[DreamM3]

I get, on average 570 km/tank on 50/50 highway and city. I did 90% highway on the weekend and got to 280 km on a 1/3 tank...

You should be getting more. I don't care what people say on here. My friend has a 2008.5 hatchback 2.3L and get about 530 a tank. I know this because I had his car for a week while he was in Texas. My ex-girlfriend's mom had a 2006 2.3L hatch and she constantly got around 530 km/tank (when a the light comes on) as well.

Ridiculous.

Fine. This is when my light turns on. Therefore I have 10 L remaining.

[el_rodento]

What is a tank? Full fuel capacity? Fueled up to the filler neck and then run till the engine stalls out? Some people fuel up early, some people run their cars until there's only fumes left in the tank.

lol, i was thinking of writing the same thing! Silv3r, when you drive on the highway are you maintaining a constant speed? During my highway commute if traffic is bad my speed can range from anywhere between 70km/h-110km/h. All that accelerating and slowing down can hurt fuel economy

[victor_t]

so I just filled up, 24 liters for 281.4 km which comes up to roughly 8.5 liters per hundred. the trip computer said 7.9. I reset the trip computer every fill-up. what makes it so off? I mean, it's an electronic injection, the car should know exactly how much fuel went in...

since I bought the car I've done 943 km and used 83 liters, that's 8.8 liters per hundred. for whatever reason when I got the car it was using more fuel, trip computer was showing more than 9 liters per hundred the first fill-up. in the mean time I learnt how to drive manual.

[slam525i]

so I just filled up, 24 liters for 281.4 km which comes up to roughly 8.5 liters per hundred. the trip computer said 7.9. I reset the trip computer every fill-up. what makes it so off? I mean, it's an electronic injection, the car should know exactly how much fuel went in...

since I bought the car I've done 943 km and used 83 liters, that's 8.8 liters per hundred. for whatever reason when I got the car it was using more fuel, trip computer was showing more than 9 liters per hundred the first fill-up. in the mean time I learnt how to drive manual.

New cars tend to use a little more fuel until it's really broken in all the way. You're also supposed to go through the rev range rather than hold a constant speed when it's new, so naturally that results in more fuel consumed.

As for why the self vs. computer calculated average consumptions differ, the most likely issue is that "full" is different every time you fuel up. Some pumps will cut off early, some cut off late, sometimes you squeeze in an extra liter to make it up to the next dollar. Keep monitoring it and it's likely to come out even overall.

Also (but a little less likely), the fuel consumption may stop calculating when you're stopped. I don't know whether this is the case in Mazdas. This shouldn't add up to much though. Idling consumes only 1.5 to 2 liters per hour.

[carsenault]

Okay. That's it. The next person who says "xxx km per tank" is going to get smacked :complain

What is a tank? Full fuel capacity? Fueled up to the filler neck and then run till the engine stalls out? Some people fuel up early, some people run their cars until there's only fumes left in the tank.

If we're going to make this meaningful, we have to use "liters/ 100 km".

46 litres of gas lasted me 380 kms, about 50/50 city and highway... works out to about 11.21 ltres per 100 km... :bang

[x_o_k_x]

it all depends on how you drive... I used to get 6.4/100km when i drived like a grandma(did a testing on how much i could get out of 1 full tank of gas, drove almost 800km a tank)... now i get 9.4/100km when i drive aggressively and dont give a damn about gas:chuckle

so if you drive nice and slow ex. spirited driving, you fuel consumption will go down.

[victor_t]

New cars tend to use a little more fuel until it's really broken in all the way.

mine's not new, it's a 2007 with 42000 km. I blame the fuel consumption on me learning how to drive manual and taking a few trips downtown (lots of hills and horrible traffic)

[emcdonnell]

If you want great fuel efficiency you should be driving a Corolla. The Mazda 3 is to much fun to drive to be good on fuel consumption. With that said the kind of fuel efficiency you do get, considering the performance, is pretty good.

BTW: The tank on the 8.5 holds 55L's if your getting 400 to 450 before the light comes on(10 to 15L left) your not doing bad. ENJOY THE RIDE
Mazda is as much about the Journey as it is about getting where your going. Remember ZOOM ZOOM....:bana

[Silv3r]

lol, i was thinking of writing the same thing! Silv3r, when you drive on the highway are you maintaining a constant speed? During my highway commute if traffic is bad my speed can range from anywhere between 70km/h-110km/h. All that accelerating and slowing down can hurt fuel economy

On my regular highway trips I maintain constant speed probably 70 % of the time and usually its around 110 km/h. I know it hurts the fuel economy but this is no different driving than I was doing im my own vehicle. I don't care how I drive, I want to get at least 420 before my light goes on.

[Silv3r]

46 litres of gas lasted me 380 kms, about 50/50 city and highway... works out to about 11.21 ltres per 100 km... :bang

I feel your pain. I think we should take a trip down the same road together to like Ottawa or Montreal and see where we end up when low fuel light comes on.

[Silv3r]

it all depends on how you drive... I used to get 6.4/100km when i drived like a grandma(did a testing on how much i could get out of 1 full tank of gas, drove almost 800km a tank)... now i get 9.4/100km when i drive aggressively and dont give a damn about gas:chuckle

so if you drive nice and slow ex. spirited driving, you fuel consumption will go down.

I would love to get 9.4 any day of the week. And I have taken it easy on several occasions and I felt no significant improvement (maybe 10/20 more km on the same amount of liters purchased before light comes on)

[Silv3r]

If you want great fuel efficiency you should be driving a Corolla. The Mazda 3 is to much fun to drive to be good on fuel consumption. With that said the kind of fuel efficiency you do get, considering the performance, is pretty good.

BTW: The tank on the 8.5 holds 55L's if your getting 400 to 450 before the light comes on(10 to 15L left) your not doing bad. ENJOY THE RIDE
Mazda is as much about the Journey as it is about getting where your going. Remember ZOOM ZOOM....:bana


I do enjoy the ride, I wish the mileage was a bit better :) A Corolla or civic would have me at 550 km easy before the light goes on, I am not expecting that at all.

Then my question is this, WHY WOULD MY LIGHT COME ON WHEN I HAVE 10-15 L LEFT and why would my km left indicator would indicate I only have 30 km if I actually have another 100-150 (yes yes, depending on how I drive). Why would my car lie to me indicating I am running out of gas when I have another 10-15 liters to go? Maybe a sensor/fuel pump issue? maybe no issue at all? But thats gay. When I see the light I feel like I must fill up but as per many of your assumptions do not have to. Might as well warn me that I have another 20 liters left.

[KenYork]

I do enjoy the ride, I wish the mileage was a bit better :) A Corolla or civic would have me at 550 km easy before the light goes on, I am not expecting that at all.

Then my question is this, WHY WOULD MY LIGHT COME ON WHEN I HAVE 10-15 L LEFT and why would my km left indicator would indicate I only have 30 km if I actually have another 100-150 (yes yes, depending on how I drive). Why would my car lie to me indicating I am running out of gas when I have another 10-15 liters to go? Maybe a sensor/fuel pump issue? maybe no issue at all? But thats gay. When I see the light I feel like I must fill up but as per many of your assumptions do not have to. Might as well warn me that I have another 20 liters left.

Caus they don't want you to run out of gas, must be because there are some people out there that are that :loco.

[carsenault]

I feel your pain. I think we should take a trip down the same road together to like Ottawa or Montreal and see where we end up when low fuel light comes on.

Wish I could do that, Im in New Brunswick though.:blush

I am planning a trip to Fredericton from Moncton at the end of May, thats about a 400 Km round trip, divided highway all the way there. That should give me a good idea of what to expect on te highway.

[Silv3r]

Caus they don't want you to run out of gas, must be because there are some people out there that are that :loco.


Yeah but if your tank is still 18% to 27% full (10-15 Ls on a 55 L tank), I hardly consider my car to be running out of gas. Every other car I have driven has the light come on when you approximately have 5 liters left giving you 40-50 km of riding fumes. It does not make sense to me. I am at around 250 km right now off that 41 L fill up earlier in the week and Im in between quarter and half a tank. Lets see when the light comes on.

[DreamM3]

Yeah but if your tank is still 18% to 27% full (10-15 Ls on a 55 L tank), I hardly consider my car to be running out of gas. Every other car I have driven has the light come on when you approximately have 5 liters left giving you 40-50 km of riding fumes. It does not make sense to me. I am at around 250 km right now off that 41 L fill up earlier in the week and Im in between quarter and half a tank. Lets see when the light comes on.

Look.. I agree with you. You should not be getting that milage. Period. It's rediculous.

I did 634/km on my last tank, and used up only 48 L. This 50/50 city/highway. that's roughly 7.7 L per 100k. I have a 5spd and drive very consistently... unusual for a 21 yr old huh?

[Iceman_F1]

Look.. I agree with you. You should not be getting that milage. Period. It's rediculous.

I did 634/km on my last tank, and used up only 48 L. This 50/50 city/highway. that's roughly 7.7 L per 100k. I have a 5spd and drive very consistently... unusual for a 21 yr old huh?

Yes, that's pretty low. However comparing your mileage to his doesn't work 100%.

You drive manual, he has auto. Do you have GT (2.3L) or the GS/GX (2.0L)? If 2.0, then that's usually even better mileage.

For a 08.5 GT Auto, it's bad, but I don't get much better myself. Sometimes I have a consistant driving style, other times I don't. My drive consists of a few semi-steep hills where I can feel the car needing a bit more power/gas to keep the speed constant so that will also affect things.

It's hard to compare mileage. Unless you take a day or something out with a friend/other mazda owner. Fillup at the same station so you both start at full and then just drive both doing the exact same route, the exact same speed, etc...THEN you'll get an idea of what the mileage is like. Until then though, it's pretty hard to compare mileage since everyone has different driving styles and drive different areas which all affect mileage.

[DreamM3]

Yes, that's pretty low. However comparing your mileage to his doesn't work 100%.

You drive manual, he has auto. Do you have GT (2.3L) or the GS/GX (2.0L)? If 2.0, then that's usually even better mileage.

For a 08.5 GT Auto, it's bad, but I don't get much better myself. Sometimes I have a consistant driving style, other times I don't. My drive consists of a few semi-steep hills where I can feel the car needing a bit more power/gas to keep the speed constant so that will also affect things.

It's hard to compare mileage. Unless you take a day or something out with a friend/other mazda owner. Fillup at the same station so you both start at full and then just drive both doing the exact same route, the exact same speed, etc...THEN you'll get an idea of what the mileage is like. Until then though, it's pretty hard to compare mileage since everyone has different driving styles and drive different areas which all affect mileage.

I have a 2.3 GT.

I agree with you, the measurement is not directly comparable, but to have the variance of approximately 200 km per tank is simply ridiculous and does not make sense in my mind.

I used to have a Jetta 2.0 L and my friend had a VR6 Jetta (both were old body style). I obviously got better milage than him, but never as signicant as in this post. Maybe 75 km a tank roughly. And trust me... he drove that car hard.

My ex-girlfriends father's Chevy Impala is getting the milage posted by some on here, and that car is a 3.2 or 3.4 L!!

Just doesn't make sense to me... I mean people can choose to milk it and look at it whatever way they want, looking for reasons for denial by comparing driving styles, consistency, and etc but if you drive your car normally and consistently, you should not be getting 400 km or less before needing to re-fuel. That's just my $.02 .

[Iceman_F1]

I have a 2.3 GT.

I agree with you, the measurement is not directly comparable, but to have the variance of approximately 200 km per tank is simply ridiculous and does not make sense in my mind.

I used to have a Jetta 2.0 L and my friend had a VR6 Jetta (both were old body style). I obviously got better milage than him, but never as signicant as in this post. Maybe 75 km a tank roughly. And trust me... he drove that car hard.

My ex-girlfriends father's Chevy Impala is getting the milage posted by some on here, and that car is a 3.2 or 3.4 L!!

Just doesn't make sense to me... I mean people can choose to milk it and look at it whatever way they want, looking for reasons for denial by comparing driving styles, consistency, and etc but if you drive your car normally and consistently, you should not be getting 400 km or less before needing to re-fuel. That's just my $.02 .

Very true. Then again, while I haven't gone 48L on my car, I am lucky to get a bit over 500km for ~44L. Could be my driving style, could be the route I drive. Who knows. It's not TERRIBLE...but could be better. Then again, my preferred speed on the highway is 120km/h...I can go lower, but I feel at east at 120 (open road, no traffic. If there's traffic, I go that speed).

IE in the morning, there's more traffic so I usually go ~100km/h. On the way home, there's a bit less so I do about 120km/h in the left lane (QEW/403 to work, 407 on the way home).

[DreamM3]

Very true. Then again, while I haven't gone 48L on my car, I am lucky to get a bit over 500km for ~44L. Could be my driving style, could be the route I drive. Who knows. It's not TERRIBLE...but could be better. Then again, my preferred speed on the highway is 120km/h...I can go lower, but I feel at east at 120 (open road, no traffic. If there's traffic, I go that speed).

IE in the morning, there's more traffic so I usually go ~100km/h. On the way home, there's a bit less so I do about 120km/h in the left lane (QEW/403 to work, 407 on the way home).

See 500km on 44L is acceptable. That's roughly 8.8 L per 100 km...That is very acceptable now that I think about it... However getting 350 or 400km is not. That just doesn't make sense...

I would be satisfied with your milage. You don't drive too hard, but you do drive it, which is good. A car is meant to be driven.

[Cardinal Fang]

Every other car I have driven has the light come on when you approximately have 5 liters left giving you 40-50 km of riding fumes.

My wife's TSX has the light come on when there is literally what looks like 1/8th of a tank of gas left. It's so ridiculous to look at the gage and see the arrow that far away from "E." When the light comes on she knows she can go to and from work at least 4 times.

[emcdonnell]

Other things to consider

the trip computer is basing its estimates on averages that only become relevent after a few thousand KMs.

The M3 fuel light does come on early

official fuel economy numbers do not reflect real world comsumption

We've talked about how we drive and how that relates to efficiency but no one has mentioned how much time they spend in stop and go traffic(more stop less go) or just idling in the line up at the drive thru or waiting for the wife to decides what shoes go with her outfit....
Some quick things to help with efficiency
-Change the airfilter
-eliminate excess weight
-regular maintenance (oil changes, tire rotations...)
-remember to swap out your winter tires
-if your going to more that 30 seconds turn off the engine insted of idling

Please add to this list if anybody has any tips/trick to improve fuel economy (other than driving like my Grandma cause that just defeats the purpose of driving a mazda)

[Iceman_F1]

Other things to consider

the trip computer is basing its estimates on averages that only become relevent after a few thousand KMs.

The M3 fuel light does come on early

official fuel economy numbers do not reflect real world comsumption

We've talked about how we drive and how that relates to efficiency but no one has mentioned how much time they spend in stop and go traffic(more stop less go) or just idling in the line up at the drive thru or waiting for the wife to decides what shoes go with her outfit....
Some quick things to help with efficiency
-Change the airfilter
-eliminate excess weight
-regular maintenance (oil changes, tire rotations...)
-remember to swap out your winter tires
-if your going to more that 30 seconds turn off the engine insted of idling

Please add to this list if anybody has any tips/trick to improve fuel economy (other than driving like my Grandma cause that just defeats the purpose of driving a mazda)

Pretty good list...though I'm left questioning for this statement "waiting for the wife to decides what shoes go with her outfit...." why you have the engine running...

[el_rodento]

Coasting towards stoplights saves a bit of gas as well since the engine uses practically no fuel when your foot is off the gas pedal.

[emcdonnell]

Pretty good list...though I'm left questioning for this statement "waiting for the wife to decides what shoes go with her outfit...." why you have the engine running...

It has happened that my wife and I were about to leave for a night out, I go start the car thinking she is right behind me, then I'm waiting... finally after a few minutes I go to check whats taking so long. It turns out that she had changed her mind about what shoes to wear and was having trouble settling on an alternative. :chuckle. I was trying to provide a vaguely amusing example

But the point was about idling in general for whatever reason

[Iceman_F1]

It has happened that my wife and I were about to leave for a night out, I go start the car thinking she is right behind me, then I'm waiting... finally after a few minutes I go to check whats taking so long. It turns out that she had changed her mind about what shoes to wear and was having trouble settling on an alternative. :chuckle. I was trying to provide a vaguely amusing example

But the point was about idling in general for whatever reason

AH XD...Yeah...I guess it COULD happen...but pretty unlikely...

[Mty Mous]

When I was going through the break-in period I was getting about 10L\100kms ... i kept an eye on the oil level and had to top it up once, this was around 3000kms ... after that, the fuel consumption started dropping slowly.

For the last 3 tanks of gas, I've been getting 8.8L\100kms ... this is MY calculations, not what the stupid ECU is telling me via the LCD screen.

I'd advise that you start tracking every tank of gas (this way it doesn't mean you can only fill up when you're empty) ... and log it somewhere ... I use www.fuelly.com cause I can access it from anywhere.

Also just put a lil note on each log if there was something from the norm for that tank of gas (like if you drove a long distance trip or were carrying a lotta weight in the car for whatever reason).

Mine's a '07 2.3L Manual GT Sedan if that matters.

I don't trust car's ECU to give me true mileage ... I just use it as guide, that's about it.

One other note, once my tank is full (I never try to overfill, just stop pumping on the first kickback) ... and I start the car, the ECU tells me I'm good for 640kms ... I've yet to ever reach that cause my personal max has been 506kms on a 44.6L fill-up.

[Iceman_F1]

When I was going through the break-in period I was getting about 10L\100kms ... i kept an eye on the oil level and had to top it up once, this was around 3000kms ... after that, the fuel consumption started dropping slowly.

For the last 3 tanks of gas, I've been getting 8.8L\100kms ... this is MY calculations, not what the stupid ECU is telling me via the LCD screen.

I'd advise that you start tracking every tank of gas (this way it doesn't mean you can only fill up when you're empty) ... and log it somewhere ... I use www.fuelly.com cause I can access it from anywhere.

Also just put a lil note on each log if there was something from the norm for that tank of gas (like if you drove a long distance trip or were carrying a lotta weight in the car for whatever reason).

Mine's a '07 2.3L Manual GT Sedan if that matters.

I don't trust car's ECU to give me true mileage ... I just use it as guide, that's about it.

One other note, once my tank is full (I never try to overfill, just stop pumping on the first kickback) ... and I start the car, the ECU tells me I'm good for 640kms ... I've yet to ever reach that cause my personal max has been 506kms on a 44.6L fill-up.

I recently started to use fuelly...however I still use my own personal excel spreadsheet...that I often export to html so I can put it on my site to see trip by trip...

Personal Fuel Tracker (http://dump.sdamv.com/Gas.html)

Nice to see your personal max has been around my personal max lol

[DreamM3]

I recently started to use fuelly...however I still use my own personal excel spreadsheet...that I often export to html so I can put it on my site to see trip by trip...

Personal Fuel Tracker (http://dump.sdamv.com/Gas.html)

Nice to see your personal max has been around my personal max lol

How do I consistently get over 5750 km per tank with an ov avg 45 L fill up? It must be the way I shift gears I suppose.

[DreamM3]

How do I consistently get over 575 km per tank with an on avg 45 L fill up? It must be the way I shift gears I suppose.

Excuse my typo please. It's early and I just got to work :bang

[Cardinal Fang]

How do I consistently get over 5750 km per tank with an ov avg 45 L fill up?

I want what he's having?

</When Harry met Sally>

[mazda lover]

Please when posting fuel efficiency tells us what size motor, what tranny, driving condition, city, highway.
Thanks

[carsenault]

Please when posting fuel efficiency tells us what size motor, what tranny, driving condition, city, highway.
Thanks

I've been averaging a bit over 11 litres per 100 Km.

I have an '05 Hatchback 2.3 L, AT. Under 75000Kms

My commute is about 50/50 with very little bumper to bumper traffic in the city part of my driving.

[degasvegas]

I drive an 2007 2.0L MT Sedan and it has about 40000km on it. At first I was getting pretty crappy mileage, but now I drive about 60/40 Hwy/City. I normally get around 500-575km per tank, it all depends on how hard I drive it.

But the huge kicker is, from what I've noticed, if you drive the 3 over 110km/hr, it really starts to burn gas hardcore. Some mornings I take the highway going 120-140km/hr and I can watch the gauge go down all the way to work. But if I keep it under 110km/hr I can still drive it hard in the city and get at least 500km a tank.

[DreamM3]

But the huge kicker is, from what I've noticed, if you drive the 3 over 110km/hr, it really starts to burn gas hardcore. Some mornings I take the highway going 120-140km/hr and I can watch the gauge go down all the way to work. But if I keep it under 110km/hr I can still drive it hard in the city and get at least 500km a tank.


+1

[Slav4ik]

on full tank my computer says I can drive 688km :) but I never ever checked how many real kms I run (too lazy) but somewhere close to that cause I do 100% highway. :)

[Silv3r]

Starting to monitor things closely as of this week. Will keep you posted.
Filled up 43.5 L yesterday. Computer indicate I had 520 KM to go (sounds good). Today I am at 84 km in or so since the fill up with 70 highway kms. I am now down to 400 km left to go according to the comp. That is already 50 KMs off computer project and will definitely be dropping.

[Slav4ik]

so I just filled up, 24 liters for 281.4 km which comes up to roughly 8.5 liters per hundred. the trip computer said 7.9. I reset the trip computer every fill-up. what makes it so off? I mean, it's an electronic injection, the car should know exactly how much fuel went in...


I beleive that the trip computer don't count the gas you spend Idling(parked) so 7.9 is your driving average consumption, and 8.5 is driving+Idling total :)

[Slav4ik]

Starting to monitor things closely as of this week. Will keep you posted.
Filled up 43.5 L yesterday. Computer indicate I had 520 KM to go (sounds good). Today I am at 84 km in or so since the fill up with 70 highway kms. I am now down to 400 km left to go according to the comp. That is already 50 KMs off computer project and will definitely be dropping.

Next time try to track how many Hrs:Min you engine was running per each fill up, It does make some difference to your fuel consumption ;)

[sunkist4338]

Next time try to track how many Hrs:Min you engine was running per each fill up, It does make some difference to your fuel consumption ;)

I know I like to get good gas mileage and have been keeping track. but counting how long your engine is running now that's a new one.

I think we all (me included )need to get a smart car and stop caring about gas mileage. lol

from what i have read the average is between 8.2 - 9.2.