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Old 15th November 2011, 22:35   #31
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Default Re: How accurate is the distance to empty

All,

I guess the other Punto & Linea owners will agree with the following, which is to say that this is true of at least the current crop of FIAT cars.

I Do not make any claim for other MID/On Board Computers/Etc.

1. The DTE is based on instantaneous FE or at most the last few KMs.
2. The DTE varies based on your current driving style.
3. Which means the DTE varies in real time - works on current FIATs.
4. If you switch between the IC (Instantaneous Consumption) & DTE
5. Then compare the IC with the Fuel left in your tank at the time, you will get the DTE shown above.
6. The above is a corroboration that for the current FIATs, DTE is based on IC.
7. It shows DTE upto the last 50 KM and then goes blank.

I have found it to be very accurate.
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Old 26th December 2011, 18:22   #32
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Default Re: How accurate is the distance to empty

Recently my Honda City showed me a range/distance to empty of 15 kms (Not that I was trying to cut it this close but I was on the expressway and there were no petrol pumps in sight). When I finally located a pump I tanked up expecting to fill up nothing less than 40 litres, given that the tank's stated capacity is 42 litres. To my surprise the tank got full with only 32 litres. I was amazed.

Cleary the range calculation was wrong. Or am I missing something here ?
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Old 26th December 2011, 19:30   #33
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I am a huge fan of the DTE display in the ford fiesta and the ford figo. They are very accurate and I am very confident with both of them. Once I had to stretch the fiesta to 3 km DTE searching for a fuel station. The fuel filled after that was just 2 litres short of tank capacity.
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Old 26th December 2011, 19:46   #34
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Default Re: How accurate is the distance to empty

Quote:
Originally Posted by eagles_ts View Post
Recently my Honda City showed me a range/distance to empty of 15 kms (Not that I was trying to cut it this close but I was on the expressway and there were no petrol pumps in sight). When I finally located a pump I tanked up expecting to fill up nothing less than 40 litres, given that the tank's stated capacity is 42 litres. To my surprise the tank got full with only 32 litres. I was amazed.

Cleary the range calculation was wrong. Or am I missing something here ?
The DTE calculation is quite dynamic, it varies with throttle input. When you saw 15 kms to empty, probably you'd have just finished driving above the economy speeds. Plus, additional load like a/c etc. will bring the FE down and consequently the DTE. Hard acceleration will bring the DTE down; coasting will put your FE at 40 kmpl. It keeps varying.

The DTE can be trusted if you are driving steady and continue to do so for a long period.

And another possibility is that the pump cut-off was not caliberated well.
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Old 26th December 2011, 19:53   #35
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Default Re: How accurate is the distance to empty

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Originally Posted by libranof1987 View Post
The DTE calculation is quite dynamic, it varies with throttle input. When you saw 15 kms to empty, probably you'd have just finished driving above the economy speeds. Plus, additional load like a/c etc. will bring the FE down and consequently the DTE. Hard acceleration will bring the DTE down; coasting will put your FE at 40 kmpl. It keeps varying.

The DTE can be trusted if you are driving steady and continue to do so for a long period.

And another possibility is that the pump cut-off was not caliberated well.

DTE is most suspect near full tank and near empty tank. Within 25% to 75% full it works pretty well for drivers who have a consistent driving style (and also consistent driving opportunity - e.g. not much of a variable mix of city/highway)

Above 75% or below 25% full, the fuel quantity measurement may have significant errors, and with an inconsistent driving style, the ltr/km estimate that the car's computers make will be totally useless for any predictions.
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Old 26th December 2011, 19:58   #36
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Default Re: How accurate is the distance to empty

Quote:
Originally Posted by PM - B View Post
All,

I guess the other Punto & Linea owners will agree with the following, which is to say that this is true of at least the current crop of FIAT cars.

I Do not make any claim for other MID/On Board Computers/Etc.

1. The DTE is based on instantaneous FE or at most the last few KMs.
2. The DTE varies based on your current driving style.
3. Which means the DTE varies in real time - works on current FIATs.
4. If you switch between the IC (Instantaneous Consumption) & DTE
5. Then compare the IC with the Fuel left in your tank at the time, you will get the DTE shown above.
6. The above is a corroboration that for the current FIATs, DTE is based on IC.
7. It shows DTE upto the last 50 KM and then goes blank.

I have found it to be very accurate.
Pretty accurate assessment. Though in my case, this works out to be a little funny, by the time I reach office from home and vice versa, a distance of about 10 km, the DTE has increased by about 30-50 kms from when I start out
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Old 12th January 2012, 11:14   #37
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Default Re: How accurate is the distance to empty

I was dropping a relative to the airport recently and my Fiesta DTE showed 65 kms.
The airport is 30 kms away and we'r running late

I then start noticing that DTE starts falling rapidly. 20 kms I had to pull over and top up as DTE showed 7kms! All this is without AC usage

As a usual practice I tank up once DTE reflects 100kms odd
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Old 12th January 2012, 11:57   #38
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Default Re: How accurate is the distance to empty

I always keep an eye on DTE in my Fiesta-D and tank up as soon as it reaches 80Kms left (reserve). Never let it below 30 so far. To me, it is so accurate.
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Old 13th June 2016, 13:49   #39
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Default Re: How accurate is the distance to empty

OOT:
Is there anyway we can add Distance To Empty(Analog/Digital) meter to old cars like mine which is 2007 Maruti Suzuki WagonR Lxi (Petrol)?
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Old 13th June 2016, 15:43   #40
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Default Re: How accurate is the distance to empty

Quote:
Originally Posted by Hatari View Post
I was dropping a relative to the airport recently and my Fiesta DTE showed 65 kms.
The airport is 30 kms away and we'r running late

I then start noticing that DTE starts falling rapidly. 20 kms I had to pull over and top up as DTE showed 7kms! All this is without AC usage

As a usual practice I tank up once DTE reflects 100kms odd
This is why sometimes "Old is Gold" and some cool new features are more misleading than guiding us!
After a few full tanks one should be able to judge on average, how many kms the car can run.
My car usually runs 550kms on a full tank - and it comes to single point just after running 400kms, and after 450km it starts blinking. I fill when there is 2 or 1 bars on the indicator.
Translated, keeping a 100 kms running worth of petrol on the car is best, just like you said, as the indicators does not exactly take into account the kind of roads we are going to run on.
If your DTE shows 100 km - and you are stuck in a stop and go traffic for one hour and just move 10 km, your range is bound to become very less.
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Old 13th June 2016, 19:39   #41
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Default Re: How accurate is the distance to empty

I always go by the fuel meter. Blinking means 3-4L left and 1 bar around 7L. Depending on where I am that decides when to fill.
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Old 14th June 2016, 17:48   #42
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Default Re: How accurate is the distance to empty

In my Beat DTE is pretty accurate. This has been tested n number of times wrt to tank to tank fill and mileage logged. By the way Beat holds 5 litres of petrol as reserve and if the mileage is 12 then @ 60KM odo the warning lamp will pop-up.

Cheers!
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Old 14th June 2016, 17:56   #43
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Default Re: How accurate is the distance to empty

Quote:
Originally Posted by libranof1987 View Post
The DTE calculation is quite dynamic, it varies with throttle input. When you saw 15 kms to empty, probably you'd have just finished driving above the economy speeds. Plus, additional load like a/c etc. will bring the FE down and consequently the DTE. Hard acceleration will bring the DTE down; coasting will put your FE at 40 kmpl. It keeps varying.

The DTE can be trusted if you are driving steady and continue to do so for a long period.

And another possibility is that the pump cut-off was not caliberated well.
I also assume manufacturers give it plenty of margin. So when it's showing 15km to empty, you can actually get a lot further. Just like your fuel gauge: there's always some fuel left even when the needle hits the E mark.
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