What would make my coolant gauge fluctuate . I thought it was the cts so I UN hooked it to see And the huge still did it. I am truly stumped.
I' d check the instrument panel connector. I had a similar problem with my LTD Crown Victoria temperature gauge. In my case the electrical connector behind the gauge was not plugged in properly. Might be tricky to check this since back side of instrument cluster is not easy to access.
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