I had a similar start to my Corvette with those codes about 50-100km after initial CEL before the CEL stopped showing up . Good thing too as my dealership is so good that they ordered a new valve body last October and have still not heard a peep about it since I dont care because my car is running great and not willing to get it ripped apart for no reason but gees I got no confidence in the service department there. Hope yours is a nothing burger too pal