Water infiltration

What is your question?

I have a Sunfire 2002 ( 2.2 OHV ) car. I try to find when i have a water infiltration )( or humidity ). If motor is full of snow or in big rain my motor turn rough at idle, is hard to start , t/c light come on and top light flashing . The spark plugs, wires, coils and ignition module are new and this is not resolve the problem. The problem disapears when engine come hot. This is why i suspect some water infiltration. T/C sensor in wheel can do that ??? or what i need to check ???