Where is the coolant temperature sensor located in a 2001 Pont Grand Prix GT? Is there a diagram anywhere that I can reference?

your water pump is stuffed . your belt is too tight, it causes the bearings in the water pump to wear to quickly, which results in your leak. when tensioning your belt, make sure the belt can be twisted at least 45 degrees

Look on front of the intake manifold near or around water outlet.

On the 3.8 liter the coolant temp sensor is right below the the thermostat in the intake manifold on the drivers side of the engine.

The thermostat is under the housing that is bolted to the intake plenum that the upper hose is attached to.

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The thermostat opens at 195 F degree, and if the cooling system runs properly, then the temperature will stay the same because the radiator will exchange the heat to air stream. If the radiator is partially obstructed, sometimes only 15%, or there are air pockets in the system, or the water pump is giving up, then the temperature will increase.

i have an 2002 grand prix gt with a bad tcc silinode sensor dont knoow where its located at...anyone that can tell me would be great

This could be the fans not working or a bad temperature sensor. If you direct wire (hotwire) the fans and they operate then the problem is very likely your temperature sensor. The temperature sensor is usually located on or near the thermostat housing. I hope this helps.

if the coolant levei is ok
then replace the low coolant sensor on the side of the rad

the temperature sending unit on a 97 grand prix 3800 gt(which is also the coolant temperature sensor) is not accurate. the sending unit part of this sensor only sends info to the guage on the dash. the coolant sensor part sends info to the computer of the car. it is located under thermostat and somewhat difficult to get at. i had put a brand new one in and my temperature on my dash is all over the place---even with good thermostat and properly bled system. when i hook up a scanner to my computer, the coolant sensor is sending the computer(ecu??) what seems to be the right temp. anywhere from 194 degrees to 217 when hot. the guage however on dash go from 160 to 260 in less than 2 minutes.

The sensor is located near the hood latch area in front of the radiator. If the temp is reading incorrectly, chances are it is defective. You can purchase a new one, they relativly inexpensive.
Disconnect the electrical connector then remove the sensor.
Good luck, let me know.
Regards,

If you changed the coolant temperature sensor and it had a 5 volt ref signal to it then you replaced the wrong part. You need to replace the coolant temperature sending unit.  The coolant temp "sensor" is an input to the ECM for your fuel injection system. The coolant temp "sending unit" is for coolant temp reading at the gauge, It is an NTC switch (negative temperature coefficient) which means as temp increases/resistance decreases.