I vote dodgy connections somewhere, most likely at the sender unit. Give
both halves of the connection a good shine-up with emery paper, tighten the
the female spade connector and see how it goes. If that doesn't help, work
you way back through all the other connectors in the circuit.
At least it is a quick, easy and free thing to check before you move onto
potentially more complex causes!
Richard & Sammy ('73 Black Tulip BGT)
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