I have just ran the test that shows up any sensors that may have been faulty, it showed the air flow meter, I then reset the ecu and drove it and now it flashes constantly when I try and re-check it, is this normal???

 

Fitted an induction kit? Subaru AFMs are like fine bone china! Vibration or dust can kill then quite easily. Not sure what the flashing light repeating means - will ask a friend of mine though, he knows Scoobs well.