Fuel Gauge Issue

I know it's been talked about here before but I can't find the thread so I thought I'd ask again.
I installed a new fuel sending unit and when I turn the key the needle does not move. It has power to it
I installed a new gauge and the needle goes backwards.
Now is this a ground problem or the sending wire problem?
I don't really feel like draining the tank to lower just for a wire.

any help will be great.

thanks

 

first rule of electrical problems, check the ground.

 

Check grounds & verify resistance

 

Are the gauge and sender meant for each other? They don't all get along.

 

Did you ground the sending unit? HRP

 

Sending unit is grounded, might need to check that ground again. It had rust and paint and might not be that clean of a ground.

Why would one gauge move and not another. Both gauges are new.

 

A fuel gage is just a resistance gage calibrated empty to full, instead of numbers. If you power the gage, then ground or open the sender wire connection, the gage should move. That indicates the gage is working. Then chase back the wire to ensure it is good condition back to the sender. Repeat the ground and open test. If the gage moves, then sender is the issue. Check that sender is grounded back to chassis. If the sender is grounded, you can check its reistance. There is not much more to do, somewhere the system has a bad connection or bad ground.

 

Is the system 6 volt or 12 volt. Original ford or after market sender and gauge? I would check for loose ground wire.

 

I just fixed my broken gas gauge. I drive a 66 fury my problem was a bad dash voltage regulator. Dont know how it works on your car but might be worth looking into it was a simple fix.