Gas Guage

[Razr]

I installed a new fuel tank sending unit on my gas tank and hooked up the gas guage to it. But for some reason if I let the truck sit over night in the morning the gas guage reads empty but if I use it in the evening again the gas guage reads were it's suppose to be(it works). Can Someone help or tell me what is the problem.

[Razr]

I installed a new fuel tank sending unit on my gas tank and hooked up the gas guage to it. But for some reason if I let the truck sit over night in the morning the gas guage reads empty but if I use it in the evening again the gas guage reads were it's suppose to be(it works). Can Someone help or tell me what is the problem. I have a 1969 GMC C25 I would also like to know what is the correct way (step by Step) on how to connect the fuel tank sending unit to back of dash

[Sinisterspeed]

Sounds like loose wire or broken wire causing a bad connection when it sits. When you start moving the truck it is causing the wire to move around and thus make connection.

Check all your connections when it reads empty.

[Longhorn Man]

I don't think I follow quite right.... it moves verses the time of day... when the ignition is off...
or it's slowly dropping but retuns to the correct reading when the key gets turned on.

[Longhorn Man]

I merged your double posts together.
direct quote from the rules;

XIV. Multiple Posting - It is simply not acceptable to post your question more than once, or to post it in more than one forum. Choose the forum that your question or post best fits in, and place it there and only there. If, after posting, you feel it should be in another forum, private message the forum Moderator and ask if they would move it for you.

It just takes too much server space if everyone double posts.