It may well be that some of the water that was thrown up has gone onto a sensor, causing it to think that something is wrong and therefore triggering the check engine light. If that's the case it should dry off if you leave the car running for a while or drive it around (assuming it's driving without any problems.) Once the sensor dries and it's happy there isn't a fault, the light should go off. If it doesn't, or the car shows any other symptoms you're concerned with, take it to an expert.
chances are that the car has been through an extremely cold spell (winter) and there hasnt been enough or strong enough anti freeze in the water, so the water in the engine froze and forced the cap out as its expanded. basicly its what there designed to do, so your engine block doesnt crack when freezeing.
the mom because not(hasnt) not(double negative has) not(hasnt) person that has not (has [double negative]) not (hasnt) set foot on the moon
it hasnt
hasnt
he hasnt
He hasnt.
he hasnt
it hasnt
she hasnt died!
She hasnt yet
it hasnt
she hasnt yet ;)