E91/E90 MPG Reading

[Le Vette]

I've had the car a few months now and noticed that the digital average MPG readout is always either 35.7 or 35.3.

Fault, or 'design feature'??

If a fault, what do I need to do to fix it?

Edited by Le Vette on Friday 4th May 17:28

[sortedcossie]

have you ever reset it? It's an average readout.

[mike9009]

If the issue is that it does not read 35.2, 35.3, 35.4, 35.5, 35.6 and 35.7 then mine is the same. It either reads 34.0 or 33.6 but never 33.8, for example.

[Prinny]

ISTR that they are ‘rounded’ figures anyway, as it’s calculated based on l/100km, and then converted. If you have the figures, and want to give it a go to make it as good as it can be, see this link (not me, but I’ve done the same thing in my cars).

http://www.bimmerforums.co.uk/forum/f18/2006-e90-3...

[Monty Python]

No - both my E92s did the same thing. The F30 has corrected that "issue".

[Le Vette]

I confess I didn't know it needed to be reset. On my last few cars it's always been a rolling average, so no intermittant reset required. I'll do that...

I'm also Interested to see the thread re the multiplication/fudge factor to calculate the average MPG. Now I know that I need to reset the MPG reading sporadically I might do a proper test and work out the actual MPG I'm getting and try to reset that number.

Gotta love modern car computers...

[Mr Tidy]

It's not a fault - all my BMWs have moved in 0.4, 0.5, 0.6 or 0.7 mpg increments on the OBC average!

Coincidentally my E91 325i is currently showing 35.7 mpg, but a few weeks ago it was on 36.4 mpg - I must have been in a hurry lately!

[Mike335i]

Same here. On a side note, I find mine surprisingly accurate too.