Is it the sending unit or fuel gauge

HI,

I am a newbie to the Chevrolet Forum so I hope this post makes sense. I have a 1969 Z28 Camaro that has something going on with either the fuel sending unit or dash fuel gauge (Center type). With about 5 gallons of fuel in the tank, it registers just over 1/2 a tank with the key off and moves to way past full with the key on. Any ideas about what is causing this malfunction would be greatly appreciated. I have not taken anything apart yet as I was hoping to get y our advice first.

Thank you,

Larry

Having experienced gauge troubles on both my '59 Chevy and '65 Mustang the answers were nobody has ever run across a bad gauge.

It's always the sender or an electrical problem and they were right.

I don't know if this will be helpful about a '69 though....... :confused:

You might want to ask at Chevy Talk >>> http://www.chevytalk.org/fusionbb/portal/index.php?

The sending unit provides the ground for the gauge through a variable resistor. Since the gauge moves to full, most likely the wire from the gauge to the sending unit is grounding to the body somewhere in between. Usually, when a sending unit goes out, the gauge reads empty because there is no ground supplied through the sending unit.

Disconnect the wire at the sender, turn the ignition switch on and ground that wire.

The gauge should immediately go to full.

If it doesn't you could try grounding the other end of that wire at the gauge.

It probably won't be as easy to get at on your car as it is on a '59.