General pre delivery mpg question

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General pre delivery mpg question

yostumpy

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Does the TA have an mpg readout on the screen, and how accurate is it. Is is on all the time, if not how is it activated.
 
Try the button on the end of the indicator stalk. It should scroll through different readouts with each press.
 
Does the TA have an mpg readout on the screen, and how accurate is it. Is is on all the time, if not how is it activated.
not to be unhelpful or anything but make sure when you get delivery of the car to ask the sales person to answer any of your questions. they did sell you the car after all!
 
The on board MPG readout is accurate so long as you're using between 2 and 25l/100km. In real life, I find it all but useless, as I spent a lot of time below that 2l/100km threshold, on my last tank it was a full 10mpg out (50 on the MFD, 60 in real life).
 
The main problems with this data, is that none of it is accurate enough for comparison with real life.

I've found that the speedometer reads 32mph at 30mph, and 75mph at 70mph. I've not checked the distance measurement but if ours is the same as other cars I've checked, they consistently read a few percent high. Remind me to check ours asap!

If the distance is reading high, it stands to reason that the fuel consumption readout will be low ......... it may be that the fuel use is wrong too?

It's all a bit useless really except for comparing one journey to another. It's like your bathroom scales ........ weigh yourself, but it doesn't matter what absolute weight you are, but you can tell if you've lost a pound or gained a pound.

Regards,
Mick
 
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The main problems with this data, is that none of it is accurate enough for comparison with real life.

I've found that the speedometer reads 32mph at 30mph, and 75mph at 70mph. I've not checked the distance measurement but if ours is the same as other cars I've checked, they consistently read a few percent high. Remind me to check ours asap!

If the distance is reading high, it stands to reason that the fuel consumption readout will be low ......... it may be that the fuel use is wrong too?

It's all a bit useless really except for comparing one journey to another. It's like your bathroom scales ........ weigh yourself, but it doesn't matter what absolute weight you are, but you can tell if you've lost a pound or gained a pound.

Regards,
Mick
so i can go 85 indicated mph with the fiat before i get nicked by the rozzers?
 
Yostumpy, the 500 has two trip recorders, each can give indepedent average mpg readings. You access and reset them via a button at the end of the wiper stalk. I compared the reading on mine with brim to brim calculations when I first got it, and found it to be within 2%.
 
so i can go 85 indicated mph with the fiat before i get nicked by the rozzers?
This morning, I was going up the A30 to Exeter.
We have a TomTom and that shows the GPS speed, and it's as accurate as GPS speed is ............. ie FAR more accurate than a car speedo.

I was doing an indicated 85mph at one point, and the TomTom said I was doing 78mph.

Ain't I naughty! :cool:

TomTom doesn't show GPS distance covered, but it connects via Blue+Me to the car. The trip distances can be displayed on-screen, but it's still the car's trip distances.

I have a Garmin Montana hand held GPS device and it will display (amongst many other things) GPS average speed and trip distance. All I need to do is switch it on, press record, and measure the ave speed and trip distance and compare it to what our 500TA says. Maybe do 20miles or more to get a good feel for the errors?

Out tomorrow, so I'll take the Montana with me. The results could then be used to modify the car's figures, so when I work out our MPG full tank-to-full tank, I'll know the TRUE figure.

If and when we do a long trip, the figures will be more accurate.

Regards,
Mick
 
This morning, I was going up the A30 to Exeter.
We have a TomTom and that shows the GPS speed, and it's as accurate as GPS speed is ............. ie FAR more accurate than a car speedo.

I was doing an indicated 85mph at one point, and the TomTom said I was doing 78mph.

Ain't I naughty! :cool:

TomTom doesn't show GPS distance covered, but it connects via Blue+Me to the car. The trip distances can be displayed on-screen, but it's still the car's trip distances.

I have a Garmin Montana hand held GPS device and it will display (amongst many other things) GPS average speed and trip distance. All I need to do is switch it on, press record, and measure the ave speed and trip distance and compare it to what our 500TA says. Maybe do 20miles or more to get a good feel for the errors?

Out tomorrow, so I'll take the Montana with me. The results could then be used to modify the car's figures, so when I work out our MPG full tank-to-full tank, I'll know the TRUE figure.

If and when we do a long trip, the figures will be more accurate.

Regards,
Mick
nice so 85 is safe = ) thanks for that i will now cruise at 85 instead of 80 in uk motorways
 
Hey, don't take my word for it.
Our 500TA returns those figures, but your car may be different!

From what I remember from when I last looked at the rules, speedometers must read within 10% of the true figure, but they must not read low. Consequently, manufacturers set them to read high-ish. Also, they like you to think you are going fast because it's glamorous. :)

Many years ago, my mate had a Cortina and he and his wife and the two of us went on a camping trip to Scotland. We drove the same distance, but he had many miles less showing at the end of the trip than I did. We discussed this endlessly.

I hit on the idea of talking to the local taxi firm and asked how they checked their mileometers and machines, and was told that from the lamp-post outside the yard, along the lane, turn left and go further and past a farm gate, there's a big powerline pole ........ and that's bang on a mile!

I tried it with my car and measured "my" mile 50 yds short. My mate tried it, and he overshot by 200yds or more!

Measured mile anyone? ;)
Mick.
 
As Mick has said, not only is the average consumption less than accurate, but the distance recorder (mileometer) is also innacurate.
That being so, even if we calculate consumption using just the distance travelled while ignoring the computer readout of average mpg, then we are only making a best guess figure.
And my bathroom scales vary depending where I put them on the floor!
 
but in reality we CAN check the reading , by using miles covered / brim to brim fill, but we can do nothing about the milo reading. Therefore one must base all calculations on this, even tho it may be a TAD high. Cant wait. Two trip readings eh! ?
 
You can still be stopped and ticketed, the limit being 70 and some coppers will happily pull you over at 78mph if they're having a bad day.


They can pull you over all they want but I very much doubt they can prosecute you at 78
 
Just start a Fuelly account. You'll get a proper accurate account of what mpg you are actually achieving. We've never believed what the range indicator shows and the speedo is inaccurate so we always drive within the TomTom indicated speed which coincidentally, is as accurate as the speed radar signs you'll find going through lots of villages.

Wife averages around 47 mpg on normal running about, mid fifties on long runs. Yes, you can drive like a snail on a cocktail of dock leaves and dandelion, but that's absolutely no fun whatsoever. Don't worry about mpg, just drive it normally and have some fun with it. If you bought or intend buying a TA based on the 'claimed' mpg figures based on artificial factory testing conditions, you'll likely be sadly disappointed.
 
Just start a Fuelly account. You'll get a proper accurate account of what mpg you are actually achieving.
No you won't.

You'll be getting a proper account of how much fuel you are using, but not the MPG figure.

Who tells Fuelly your mileage?
You do.

Where do you get your mileage figure from?
From your car.

How far out is that mileage figure?
Dunno, and neither do you.

As I say, I'm going to check using my Garmin Montana and compare what my 500TA says with respect to the true figure.

Watch this space,
Mick.
 
No you won't.

You'll be getting a proper account of how much fuel you are using, but not the MPG figure.

Who tells Fuelly your mileage?
You do.

Where do you get your mileage figure from?
From your car.

How far out is that mileage figure?
Dunno, and neither do you.

As I say, I'm going to check using my Garmin Montana and compare what my 500TA says with respect to the true figure.

Watch this space,
Mick.

Mick, you've completely lost me here. You put your odometer reading in, put in the details from the fuel receipt and it works it all out for you, including the mpg. It has produced a table of mpg figures for every one of the 38 fill ups we've done and I've absolutely no reason to doubt the calculations produced. Are you saying Fuelly is inaccurate? Certainly the information we put in isn't inaccurate, we write the mileage on the fuel receipt at every fill up, and input the fuel in down to the last decimal place. The only thing we can't account for, is the accuracy of the pump the fuel comes out of. So I'm clearly being somewhat stupid here and you'd have to explain it to me in a far easier way, coz you've got me stumped!

I apologise in advance to all those hypermiling addicts out there. I personally can't understand why folk do it, but I respect those that want to, it's just not my idea of a 'hobby'. This whole coasting down hill for as long as possible....why?? I guess for someone like myself who drives 237 miles a day, 5 days a week, I'm just not in that 'zone' lol!
 
I think he is saying , in a roundabout way, that as the milometer is not ''100%'' accurate, then your Fuelly wont be accurate either. But for me if everyone else uses the cars milo, and works out on Fuelly, then if I do same its a direct comparison to others, but not 100% accurate, (prob 95% ish, which is good enough for me, and you probably}
 
You put the odometer reading in.
That is the point I'm making.

Earlier, you said that you get an accurate MPG figure.
I say you get an accurate fuel consumption figure because you don't know your mileage. You THINK you know your mileage, and it may well be correct, but it may not be correct. It could be out by (maybe as much as) 10%.

Whatever the error, it is constant and additive. Over 10,000 miles, you could have done as much as 11,000 miles or as few as 9,000 miles. You personally have no way of knowing one way or another. I reckon it's more like 2% out at a guess. ie 10,200 miles down to 9,800 miles. Either way, it'll play havoc with any overall MPG figures.

Hopefully over the next few journeys, I'll have a conversion for our car. Maybe the odometer is dead on accurate. I don't know as yet.

Regards,
Mick.
 
Ok, get you on the odometer accuracy lark, but from that perspective, I live exactly, and I do mean exactly, one mile from the A38, so from my driveway to the junction where it joins the A38, on my walking pedometer, my pushbike speedo, my Saab odometer, the TA odometer and finally TomTom, they all come out the same, so I'm guessing the TA's odometer isn't that inaccurate. ;)
 
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