Guys, the check engine light on F7's means business. If that light comes on it means the coolant is over 176F and will soon boil. If it boils, the water pump can cavitate, and if the water pump cavitates, your engine will seize. When you see the light DON'T keep truckin like nothing is wrong, or you may end up on the wrong side of a towrope. This is a serious post and put it in your memory cells so that it doesn't happen to you!