I had this when my car was about 2 months old. The MIL lamp came on during one of those incredibly sudden downpours of rain when you have to slow down to a crawl. It wouldn't reset after a few engine cycles so it went into the garage. They took a few days to tell me nothing was wrong, then a few days later it went back in and they replaced the lambda sensor. For the next few months I got used to the strobe effect of the MIL lamp, but the engine was always running fine and it cleared itself. Then it stayed on permanently, so it went in and they changed the lambda sensor and wiring (which had to come from Italy). I picked the car up and on the way home the MIL lamp came on. It went into another garage and they changed the camshaft sensor which had to come from Italy. Incidentally, the car has also had a new rear screen and front washer assembly. There's trim falling down from the ceiling in the boot, the carpets are coming away from the footwells (I peered behind the carpet in the driver's footwell and there was an elastic band holding it up - I kid you not!)
It's latest trick is a bit hard to explain, but every now and then, perhaps twice a week on my commute, on part throttle, usually in a higher gear, medium revs, the power just dies and the car won't accelerate, but it doesn't decelerate on engine braking. It feels like you've hit a soft rev limiter (below 3k revs!). If you back off and re-apply the throttle it clears it. No MIL lamp so presumably no fault codes so the stealers won't have a clue what's wrong.
Shame Alfa have done nothing to change their poor reputation and the cars still won't work properly. I don't enjoy running the car.