When I turn my key on in my 40 Buick super,my fuel gauge goes from empty to past full. Where do I start diagnosing the problem? Can I access the sending unit wire in the trunk? I just bought the car and the gauge was not working.
I just went through this very same thing on my '37. If you follow along from "I ran out of gas" to the next few posts detailing how the problem was diagnosed and fixed I think it'll help you out. I received great advice from many of the same people (Bloo) giving you input. They know their stuff.
Here's the link starting when I ran out of gas and it continues on from there:
Here's the posts detailing tank removal and diagnosis and repair of the sender in