'04 V70 168 Geartronic 5 speed - realistic mpg?

[stimperley]

We have had the above spec V70 Sport for about 18 months now and, compared with some of the very impressive figures I have seen mentioned on here, I have always been slightly disappointed by its mpg. When I test drove it the computer was showing 41mpg average and I happily assumed this was the long term figure. However I now know that this can easily be achieved by resetting the computer and going for a leisurely motorway trundle. In reality, it was reading 39mpg when we picked it up a few days later and has continued to ever so gradually descend ever since. I thought that it had settled around the 36mpg mark a few months ago but now it is showing 33.1mpg. Its not been reset for several months.

Does anyone think this might be indicative of a problem?

Car has done nearly 140k, performs great - although I haven't driven another of the same spec to compare, been properly serviced twice by us (evidence of neglect before that though), I cleaned out the EGR plenum which was completely furred up but I am sceptical that this contributes much to general running. I did find that the air flow meter was also badly clogged. Sprayed lots of carb cleaner through it which cleaned the mesh completely & I think that cured the previously very smoky exhaust under load but, surprisingly, didn't notice performance improvement and mpg has continued to trickle downwards. I took great care with the afm but could the spray have damaged it, would there be other symptoms?

Admittedly the other factor is my good wife's inability to grasp the concept of driving economically and she does most of the mileage. She just plonks her foot on the loud pedal and leaves it there until at the last moment she has to hit the brakes ... Coupled with the gearbox's eagerness to perform - it is really quite difficult to keep it in top gear on local winding/hilly roads - I suspect this is a major factor, but she does do about 20 dual carraigeway miles a day too.

I suspect a manual gearbox would be a lot better for extracting higher mileages and I'm willing to accept that and the above are all it comes down to, but all thoughts/contributions gratefuly received.

Simon