temp gauge not working

I changed my AC pump and the serpentine belt. Now my temp gauge stopped working and car runs like ****znit. Does releasing the pressure in the ac system do something to the car? Also is there a fuse or something for the temp gauge or a way to diagnose why it stopped working? Might be a good time for me to get some autometer gauges.
 
when I swapped intakes I lost my Temp Sending Unit. It won't eefect the way the car runs, but it gave me a completley different reading. The old one always stopped 1/3 the way up the temp gauge, the new one revealed that i was running allot hotter. The new one also gave a much faster reading... $14 Ford Dealership..
 
Resurrecting this old thread because I never figured out why it is not working. But I did notice that the guage is actually kinda working. When I turn the car on it goes up a little then it goes down. But it appears to be trying to work but it is going the opposite direction (below the lowest mark)

Any ideas why that is happening?
 
Check the connector on the sensor. It just pushes on and sometimes does not make that great of a connection. I would clean it and tighten it and see if it works any better.

Good Luck.