Ignore trying any version of "gauge fix" like above until find why doesn't work to read engine temp.
read Ω on sender w/ engine cold and warm/hot.
Sender output pin and block should see Ω change as engine gets warm. Don't bother exact Ω.
Wire off sender gauge should peg and stay until sender get connected again.
try those first.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave