Chevrolet Repair: Chevy Celebrity Cooling Fan Sensor Location, coolant temp, chevy celebrity

Question
I am trying to repair my son's 1988 2.8L FI Chevy Celebrity.  Aside from a coolant leak from the engine block that I reluctantly used a "Stop Leak" solution to fix, I noticed that the cooling fan on the radiator is not working.  This was probably the source of overheating that led to the leak.  When supplied with 12V, the fan works so I assume it is the sensor/switch on the engine block that is malfunctioning.  The Haynes manual on the car does not address the location of this switch.  I know that there are two sensors, one for the cooling fan and one for the temperature gauge on the dash. Any hints on where the one for the cooling fan is located?

Answer
Hi Ron, First of all this fan doesn't come on until the coolant temp is around 230 degress. The sensor is the same sensor the computer uses for engine temp. The computer turns the fan relay on to make the fan work. This sensor is near the thermostat housing. I would the engine at idle until it reaches 230 and watch for the fan to come on. This could take 20 to 30 minutes.

Hope this helps

Mark