can anyone tell me where the water Temp sensor is on a 91 max? single cam..

 

I am assuming that you are talking about the coolant temperature sensor. http://www.autozone.com/servlet/UiBr...3d801f4731.jsp
This shows either the VE or VQ motor but at least it gives you an idea of what it looks like.

 

its on the pipe that returns coolant to the radiator. follow the hose on the top passenger side of the radiator back to the aluminum pipe and there will be two sensors sticking out of the pipe. both are coolant temperature sensors but one is used for the gauge whereas the other is used for the ecu. the rear sensor with the square piece on it is the sensor for the ecu while the front sensor with the blade connector is for the gauge.