Edited: another fuel/temp gauge thread, but turns out the harness is melted together
It never hurts to make sure you have good connections, but that won’t solve your aftermarket fuel gauge problems.
The basic issue is that the A body gas tank has a big scoop out of it on about the top half to clear the spare tire well. Since the top half of the tank holds a lot less gas, the fuel level drops a lot faster in the tank. The factory senders are non linear to account for the tank shape. The float arms are also much longer than the aftermarket.
The aftermarket senders a a linear design and do not account for the tank shape, so they don’t work properly. The float arms are much shorter as well. The gauge drops fast from full, because there is not much fuel in the top half of the tank. The float arm length also influences this.
Below are a couple of charts I pirated from somebody else on the forum to illustrate this.
It never hurts to make sure you have good connections, but that won’t solve your aftermarket fuel gauge problems.
The basic issue is that the A body gas tank has a big scoop out of it on about the top half to clear the spare tire well. Since the top half of the tank holds a lot less gas, the fuel level drops a lot faster in the tank. The factory senders are non linear to account for the tank shape. The float arms are also much longer than the aftermarket.
The aftermarket senders a a linear design and do not account for the tank shape, so they don’t work properly. The float arms are much shorter as well. The gauge drops fast from full, because there is not much fuel in the top half of the tank. The float arm length also influences this.
Below are a couple of charts I pirated from somebody else on the forum to illustrate this.
