Blimey four replies already including Ned himself, you guys work fast. Thanks for the advice folks.
The injectors may well be an issue, however the garage I purchased it from had all four replaced along with a full sevice and cam belt change by autolusso's in march of this year before I bought the car.
Its never overheated while I've owned it in fact the needle always quickly climbs to and stays firmly at 90 and never budges an inch no matter the circumstances. Having said that it does puff out a bit of blue if gunned on start up from cold. (not that I make a habbit of doing this by the way)
The oil is always topped up with the proper 10w60 stuff (castrol edge).
Ned, you pointed out the supermarket fuel thing, the gt isn't my first alfa and im aware of a few of the do's and don'ts. I do try and avoid filling up at sainsburys, tescos etc but ive never quite understood why. poor quality? Would this effect oil usage.
In any case looks like visit to lusso's is in order.
Thanks again for the speedy feedback