MPG Faulty?

Kerplunk

Kerplunk

Kerplunk

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Joined
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Bournemouth tbh
Hi guys

My A3's MPG seems to be jumping around from 40.0mpg to 72.0mpg to 140.mpg then to - - - ?

My mates Golf does it aswell?


Is this normal?:confused: How does it get a steady reading?
 
Put foot back on accelerator.

Seriously though it sounds like you're looking at the instant consumption figure rather than the average over the last x miles.
 
Spunkey said:
Put foot back on accelerator.

Seriously though it sounds like you're looking at the instant consumption figure rather than the average over the last x miles.
Click to expand...

+1

:D Did make me chuckle though, I guess if you aren't in the 'know' it might look odd..
 
What is the instant consumption then? and why does it vary so much? Is that not what I should be looking at?

This is my first car with an MPG in it lol, not had it long! :p
 
Instant is just that, if you nail the throttle it'll say 'omgz you're using loads', if you ease off and engine brake it'll say 'oooh awesome mpg'.

You want to be looking at average for tank/journey.

EDIT: Example...

Below the rev counter I have 'instant/live mpg'

DSC_9458.jpg



But on the OBC I have average MPG...

DSC_9571.jpg
 
Yep, Instant is the exact fuel consumption you are doing at that very 'instant'.. and depends on speed/throttle/road etc..

Going up a hill it'll be low, lifting off and going down a hill with be very high, and sat in traffic it might show '---' as MPG is almost meaningless if you aren't actually moving..

And as everyone is pointing out, Average is the one you want.

:)


This is my first car with an MPG in it
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It's known as a fuel/Trip computer, MPG = Miles Per Gallon which doesn't make much sense, although we get what you are saying, as it's telling you your MPG..

That just made me chuckle a little, in a silly way!!!

Hey my car has an MPH in it too! (otherwise known as a Speedo..) :)
 
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Press one end of the rocker button on the end of the stalk on the right I think it's the windscreen wiper stalk. It will cycle through the available displays (ave mpg, instant mpg, journey time, miles from start, average speed).

If you press the button that is on the bottom edge of the stalk it will display the menu where you can select what to display.
 
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Ok guys, I understand the idea now, but the readouts are really random on the instant consumption, like it changes every 2 seconds going down a 30MPH road? With big variance :confused:

Normal?
 
Kerplunk said:
Ok guys, I understand the idea now, but the readouts are really random, like it changes every 2 seconds going down a 30MPH road? With big variance :confused:
Click to expand...

In my car, if I'm on a flat road, with a steady unchanging throttle, and a steady speed, mine will fluctuate by only a couple of MPH..

But whilst bimbling around, it'll go from 10-20 odd MPG (whilst accelerating up to speed etc) to 120 odd MPG (steady 40 MPH) all the time..

It should be possible to get a reasonably steady reading, but only, as I said, if you are at a constant speed/throttle position on a road that isn't changing in gradient.

When you drive along, some people regulate their speed by slightly slowing a few MPH, then speeding up a little to keep themselves around their chosen speed, every time you increase your speed a little, you are accelerating, and the instant MPG figure will probably drop quite low indeed, once you are at speed and letting off the throttle a little, it'll jump right up again.. it depends on how you drive, as long as it ties in with what you are doing with throttle and accelerating/decelerating, it's normal..
 
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Kerplunk said:
Ok guys, I understand the idea now, but the readouts are really random on the instant consumption,
Click to expand...

They aren't random. Even if you think you are keeping a fairly steady speed the instantaneous fuel consumption will vary significantly with even slight inclines, head or tail winds etc.
 
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