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It appears instead of giving an average on my MPG it shows what I'm currently using it does keep an average at all. I have read the manual and its no help. Anyone know if it can be switched
 

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Are you able to cycle through the various functions pressing the right-side instrument knob?

Current Fuel Consumption
Average Fuel Consumption
Range (Distance to Empty)
Average Speed
...I might be forgetting one:confused:

Jason
 

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The "average" function was not there in 2006. It appeared in either 2007 or 2008, I can't remember which. The display only showed "instantaneous" in 2006.
 

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Yes, they got some negative feedback about that. It was fixed in '07. And the lack of an inside fuel door release.

I'd like to know if anyone knows if the '06 mileage readout can be modified or replaced to show average mileage. Probably this is easier to do with a bluetooth OBDII adapter and a smart phone app.
 

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If others are as inaccurate as mine I wouldn't bother. My readout error is scattered evenly between about 0.45 to 1.0 L/100km too high per tank. You may as well just do the math when you fill up.
 

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The "average" function was not there in 2006. It appeared in either 2007 or 2008, I can't remember which. The display only showed "instantaneous" in 2006.
Arh, maybe not in your market.. My 2006 does have the AVG function, along with instantaneous, and "nothing"

I can also delete the average. Mine is NOT a rolling average, but an all time average since last reset. To reset, I hold down the function button next to the display for a couple of seconds while having average mode selected, it then shows - - until I start driving, and it starts to show the average after about 500m/ half a mile driven.
 

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Avg on mine is some random number generated when I push the button. I have full records of all fuel thats gone into my car since new. The onboard computer has 'never' been right.
 

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Avg on mine is some random number generated when I push the button. I have full records of all fuel thats gone into my car since new. The onboard computer has 'never' been right.
Have you tried resetting the AVG display when you fill up the tank?

I reset mine every time, and it is always reasonable accurate (+- 0.5L/100km)

Our 2009 Swift has the same display, and the exact same functions, but it is even more precise. maybe +-0.2L/100km
 

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I have tried, no real change in accuracy. Being wrong by .5l/100 it may as well be out by 5. I don't see any point in the readout actually. If you reset at every tank why not just do the calculations manually anyway?
I think it's nothing more than a gimmick and completely unreliable.
 

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Suzuki should have provided a way to offset the displayed number as I think the error is fairly consistent. In my case a significant variation in calculated L/100km occurs because I don't fill up to the same point, just let it click off.

The attached graph shows calculated L/100km for all tanks (in red) that was matched with each displayed average over the tank (in blue.) A vertical spread of 0.6 L in 10 L equates to about +/- 1.2 L on the fill-up of 40 L, easily blamed on fill technique.

The graph I posted before shows that the error averages out over 40 tanks to +0.67. If I simply adjust the readout by that number I think it would be accurate within the display's 1/10 resolution.
 

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Kiwi,
The amount you put in the tank shouldn't matter. The ECU couldn't use the gauge for the calculation because fuel tank level indications are notoriously inaccurate. The ECU should be basing its calculations on very exact figures gathered from the fuel injection system. The ECU is supposed to be metering fuel to each injector precicely. The ECU should know to within a few ml exactly how much fuel it has delivered and it has access to the same distance traveled into we have.
It should be able to calculate correctly.
 

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Kiwi,
The amount you put in the tank shouldn't matter. The ECU couldn't use the gauge for the calculation because fuel tank level indications are notoriously inaccurate. The ECU should be basing its calculations on very exact figures gathered from the fuel injection system. The ECU is supposed to be metering fuel to each injector precicely. The ECU should know to within a few ml exactly how much fuel it has delivered and it has access to the same distance traveled into we have.
It should be able to calculate correctly.
Kev, yes of course we all know the fuel gauge is inaccurate which is why I haven't mentioned it in my post. My point was that the variation in error I've seen can be explained by the varying fill levels at the filler opening due to the gas pump's automatic shutoff.
The ECU only needs injector open time and calibration factor, per distance traveled to calculate fuel economy. The error on that side is most likely due to variation in fuel pressure regulation which affects the calibration factor. The ECU does not know exactly how much fuel is injected which is why it needs a closed loop control and why the readout is not accurate.
 

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My point was that the variation in error I've seen can be explained by the varying fill levels at the filler opening due to the gas pump's automatic shutoff.
This is the bit I don't understand. The ECU wouldn't know or care how much you put in the tank. Any correlation you see is purely coincidence. The fuel gauge, even if it was a perfectly calibrated instrument, can never be accurate enough. Simply parking on anything less than a perfectly flat surface will introduce inaccuracies.
The instantaneous usage and average use must be calculated via injector opening times.
 

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The fuel gauge, even if it was a perfectly calibrated instrument, can never be accurate enough...
Hi again Kev, I'm not sure why you keep mentioning the fuel gauge? There must be a misunderstanding there. Nothing here is relevant to the fuel gauge - not the digital economy readout nor how the tank is filled to the top. It simply reads the current passing through the pair of resistive float levels and stands alone in its uselessness.

You are right that the ECU doesn't care about how much you put in the tank and yes, the ECU adds up injector times but I have no disagreement on those points. I'm comparing calculated economy from the petrol station pump and odometer with the readout set to cumulative average over the same tank. Correlation between those two is entirely expected. It's the delta and it's spread that I'm trying to analyse.
 

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I must be misunderstanding you. You mentioned different amounts going into the tank when filling. What part does that play?
 

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If I let the pump click off automatically I get less fuel in the tank than if I top it off manually. When I do the math, if I topped it off it appears that I used more fuel on that last tank and my calculated economy will be lower.
Mostly I rely on the automatic shutoff, accepting there will be some variation.

As you've mentioned the readout doesn't care how I fill the tank. It is being re-zeroed at that time though. However I don't know if the readout is accurate or consistent, so the manual calculation is the best data I have for actual fuel economy.

Over 40 tanks my error between the calculation and the readout has settled to about +0.67 L/100km on average, the readout being higher.

If I look at the data more closely, particularly the spread of all tank fills for each readout value, 9.6 for example, that spread is going to reflect the filling variation in addition to any unknown errors in the way the ECU measures economy. But because that spread roughly matches what I think is the filling variation, I'm taking a leap of faith concluding that the readout is actually pretty consistent, just offset from the correct value by 0.67.

Hope that's clear, too wordy I know!
 

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I now understand, your referring to your manual calcs.
My experience with the displayed value is, just as a stopped clock is correct twice a day, the display occasionally gets it right. I have seen an avg of something like 27l/100 displayed. This was months after a reset and just after refilling with about 45L of fuel. The numbers stayed like that for about 700km and 2 more fills. This was during an extended outback trip where my actual fuel use averaged 12.56. Clearly ridiculous.
To be honest, I haven't looked at the avg display for prob a year or more.
 

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I have tried, no real change in accuracy. Being wrong by .5l/100 it may as well be out by 5. I don't see any point in the readout actually. If you reset at every tank why not just do the calculations manually anyway?
I think it's nothing more than a gimmick and completely unreliable.
I do find it very useful.

For instance, it will tell me if I'm about to run out of petrol or not, since I prefer not to trust the fuel gauge.

Going bush, I get a range of anything between 15L/100km to 30L/100km depending on the terrain. Looking at the average consumption on that tank of fuel, will give me a simple answer to how far I can go.

I also find it interesting during the normal work days, as I see a HUGE difference in petrol quality, as expressed in average consumption. For instance, I get terrible mileage using ANY petrol from Shell, often 50km less on one tank, compared to a reasonable better outcome from Caltex, which is again beaten by BP.

Comparing economy is a breeze using that gauge, as I reset it every time.
 

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@ dkguffe: Mate, I got the same 2006 2.7ltr car like you (although built in 2005!) but I only have 3 options; L/100km , km/L , and blank
Should there be more?
 
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