okay just an update in case anyone else encounters this same problem-
I pulled out my spark plugs (which seemed dry) blasted the inside with compressed air - put it all back together got a new K&N air filter (Found out mine had sucked up a sh*t load of water, just didn't notice because the stock box has small holes down the bottom which just drained the water out) and now it runs perfect again
I did actually have a CAI installed that was running into the stock box - This is because the day before I had actually removed the connecting pipe and replaced it with the stock box intake, just left the pod and pipe there bcoz its bolted in and i tent to change between the two when i get bored... which was unfortunate.
Cheers for all the help fellaz.