Grant,
From my experience not all of the replacement temp senders have the correct ohm rating that is compatable with the gauge. We went through about 5 of them before finding one that would work correctly. One of them acted like a tachometer, when you reved up the engine the gauge would peg, let off and it would go back down. Sometimes you can figure it out through trial & error, but it's frustrating. Remove the sealant and see if it helps.
Fred
