Hi there. I bought a mk 4 sxi 2 weeks ago and had it serviced yesterday. I brought to the mechanics attention that the immobiliser light ( the one with the car and spanner ) comes up on the dash sometimes. anyway he said he'd get rid of it and did the diagnosis on the machine. nothing came up. anyway, when he got to changing my spark plugs he noticed that the issue was that oil had somehow got into the plugs and was the reason that it would sometimes not start. he cleaned as much oil out as he could and then it seemed to work all fine. i drove to work and it was better than ever. then i turned it on to drive home and the B*****D light has come on again, not only that, but INSP has come up on the dashboard everytime i turn the key. im starting to get worried. what should i do now?