MPG readings take off 4MPG perhaps!!

[brittas]

I have a 04 2.5i SE. From filling up and working out MPG calculations from miles travelled I think the trip MPG reading on board is about 4 MPG out. When my trip says 30MPG over a tank full Its really 26MPG....
A shame its not out the other way lol. Never mind you don't buy a v6 petrol for the economy. :evil:...whoops straight 6 I should know I just done plug change :?

 

[pvr]

A V6, that is a very special model you have over there, that might explain it.


... the rest of us have straight six

 

[mikedav]

It's not a V6 ...

EDIT: Gazumped

But yeah the OBC is incredibly inaccurate, hence why you get reports from some of 40MPG on a 3.0, etc etc...easy to do if you reset it while at 70MPH on the motorway. If you do the sums and work it out pump-pump, it's usually lower

 

[a11y]

I think the OBC gets more accurate if you DON'T reset it after every fill - it tends to settle down. I always reset mine on each fill-up though and find it does over-read quite a bit. But as said I didn't buy my Z4 for economy purposes, although it still does better mpg than my old Civic Type R hot hatch...