[Carbuff]

I think it was just the TCS (traction control system) doing it's job in the rain. Maybe the throttle body is sticking? Would result in heavy acceleration and wheelspin. Wheelspin makes the TCS system (and light) engage.

You have any service records for that car? Don't know why the splash shield would be off ... but the tranny fluid should be replaced, I'd say, and I would want to know when the timing belt was replaced (due at 100K miles).