Tim, I think I understand now. So, run a extra "test" ground from the ground on the sender unit to the ground on the frame or gas line, and then also run a "extra" ground from the gas gauge to the ground on the battery. Then see if the gauge changes, then I can remove one of the grounds, and that should tell me which side is not ground properly, either the gas guage or the sender unit. Is this what you mean? I sure hope so. Sometimes trying to read things like this will confuse me more, but this is a big help to me.
What do you think about my test light showing no activity on the sender unit? That makes me wonder if there is some "break" in the line somewhere I can't see, like on the lower firewall where the harness comes out at.
I have read the past posts, but I still would like all the help I can get!!
