problems with fuel gauge(float)

[starfish]

I'm having some weird problems with the float in my tank.When driving the gauge woud jump all the way past full(with 1/4 tank of gas).At the same time the temp gauge would go all the way up.I took the float out and had it all the way down and the gauge went back to normal.As soon as I move the float just alittle bit, the gauge jumps all the way up again.Ok so there must be a short in the float, so I ordered a new one.But would the fuel level sender shortin out effect my temp gauge?

 

[Fordum]

It might. A normal sending unit never goes all the way to a direct short. It goes between two resistances.
If your resistor is shorted, it might load down the power supply for the instrument cluster and cause problems.

You could also have a ground problem with the cluster and it is getting its ground from the sending unit, or the temp sending unit.

If you have an ohmmeter, you can measure the resistance between the housing of the float unit and the connect point of the gauge.

The resistance it should be is somewhere on the forum, I'm sure, but i don't have it off the top of my head.
Someone else will know I'm sure.

 

[4X4HIGH]

Most GM fuel senders are 0-90 ohms

 

[Fordum]

Most GM fuel senders are 0-90 ohms

Yep, as soon as I read that, it clicked. Thanks for setting me straight.
Don't know why I could not remember it.

That eliminates the short idea, since it goes to zero.
I was thinking temp sending units which stay in a range.

That makes it most likely a ground problem or corrosion causing a cross connection in the panel or wiring.

Of course, the PO might have done something weird with the wiring too......

 

[bot0611]

Might be dumb but have ou checket the ground wire... i had a similar issue and it was the ground that was loose.