I'm new here... and don't know much about Maserati (yet)... but first off... I would change your oil... do it yourself. Check oil for gas in it. It'll seperate from the oil (oil & water don't mix right?).
Have you been burning oil?
If both those are yes... could be leaking through at the pistons or head gasket. Neither good answers. Gas can be more likely to seep through if you've been driving the engine cold often (no heat = no expansion = worse seal).
Either way, gas in oil = bad, because it breaks down the viscosity of the oil. So step one is change it, step 2, let it warm up before driving and see if you still have the problem. step 3 is take it in to get looked at.