The coolant housing at top of engine is made of plastic. This cracked. For awhile it was a slight seep of coolant coming from the bolt threads. But then later it cracked more and fluid spewed from the housing all over engine causing a loss of fluid and risk to engine health. It was necessary for the mechanic to replace the housing and gasket. I was without my car for 1 day. It was a dealer only part, and the dealer had it in stock. If they had to order, it would have been longer with no car.