1996 Jaguar XJ6 • 90,000 miles

My Temp gauge seems to be very eratic. When I drive the car the gauge is fine. When I stop or put the car in park for a minute, the rage goes through the roof. When I turn the car off then on again, the temp gauge resets to give me a normal reading. The other day I also noticed the gauge running hot while driving up-hill, when I started going downhill, the gauge went down again, and gave me a perfect reading, once I was driving on a level surface. Is there some sort of ballast that may be malfunctioning, or possibly the Thermostat control sensor? I changed out the thermostat so I now it's not there
November 20, 2012.

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