Somewhere, there is a chart of resistance vs. temp for that sensor, but, I can't come up with it just offhand.... Might wanna try and find that, and see which is wrong, the sensor, or the gauge.

 

Another possibility is just a goofy sensor. I went through 3 brand new sensors on my 97 before I got one that was close. The one I have now shows 20 degrees above actual temp. I know it's off, and how much, so I don't worry about it.

 

This is what I think it is. I work at a auto parts store so ill take the sensor out and warranty it an hope it gets closer to where is should be on the gauge with a new sensor . This one is reading about 20 to 30 degrees above actual temp.