[rhandwor]

You have one sensor for the computer system and another one for the gage.
Look at the parts store for the one for the computer system. I've also found them coated with scale. If you have a manual you can check the ohm readings on the sensor.
The sensor for the gage I would use a piece of no.14 solid copper wire about 4 to 6 inches long. Touch one end to the block and the other end to the wire. The gage should peg with somebody watching it and the ignition on. If it doesn't peg install a new gage if partially ohm the wire. I've found some parts store sending units don't work and installed a new dealer part and they worked. Feel both radiator hoses and make sure they are hot you may have a bad new thermostat. I heat up a old cup of water and imerse them to be certain they work before installing.