Hi there all

Im new to this but thought id give it a try... :-)

I have recently purchased the above, lovelly car, 2 things, one I hope
I have just sorted (damn alarm systems!) the other is starting to
annoy.
It seems to have an intermitent lack of power when running during
gentle but steady acceleration, it starts first time, ticks over fine,
doesnt get hot etc etc.
When gently accelerating from between 55-70mph in 4th or 5th gear (4th
gear 55-68mph and 5th 60-76mph,...ish) (occasionally in 3rd 35-45mph)
the cars 'lumps' for lack of a better word, almost short hesitations,
and if I put the accelorator fully down not alot happens, it will
gradually pick up, then clear and off she goes.
During steady calm acceleration when the engine is reving high enough
to pull away at a pace a V6 should, ie to pull out on a dual cariage
way to overtake quickly but not like a bat out of hell it will remain
lumpy, and as speed slowly matchs revs and required acceleration it
goes and will accelerate fine. If it is floored in say 3rd at 50ish or
4th at 70ish it is fine and prety rapid.

I have had the plugs etc checked, it doesnt tick over lumpy at all, so
not mis-fire suspected, the  control system has picked up on a
intermitent air flow meter error, but the garage is not sure its this.

The car drove home fine when I picked it up, was very low on fuel (fuel
light on even when sitting) during both viewings and test drive (upto
120mph).
I thought crap in injector etc, have sprayed cleaner in through air
box, into plenam chamber, cleaned/lubricated throttle linkage, checked
breather pipes etc and put injector/petrol treatment through it, have
also run 2 tanks of higher grade 'performance' unleaded.

Any ideas or answers would be great.

Much appreciated and sorry for the extensive waffle ;-)

N