As I posted yesterday, Monday evening was spent replacing the leaky float in Glinda’s gas tank. Yesterday afternoon I bugged out of work at 4 and was pouring gas into Glinda’s tank by 5. After putting about three gallons in, I turned the ignition key to ON and watched while the gas gauge needle did … NOTHING. I had it in my head that the capacity of the tank was twelve gallons, so a fourth of that should at least move the needle above E. As a check of the gauge, I disconnected the sender and measured resistance across it - about 3 ohms – the same value I got for a completely empty tank.
Thinking the new float was bad or I'd put it on backwards and it had stuck to the wall of the tank, I siphoned out the fuel in the tank and removed the sender - the float was dry and empty; measured the resistance across the sender while manually moving the arm – it went from about 3 ohms to about 90 ohms; plugged the sender back in; grounded the sender's black wire; and had a friend watch the gauge as I manually moved the arm with the sender in the same orientation as it would be in the tank - the needle moved just as it should. By the way, as soon as I disconnected the sender, the gauge needle did go to well above F. I then flipped the float around (even though it now disagreed with the manual), reinstalled everything, poured about three gallons in - needled didn't move from E.
Okay, everything checked out as functional, but the stubborn donkey-esque needle wouldn’t be budged. My next step was to go whining on the internet and see what stupid error I was making. Responses came back that four gallons was not enough to move the float. GM meant it to be that way. Since the tank holds 14 gallons (not 12), once the needle reaches E, you’ve still got three to four gallons of reserve fuel.
Excellent – I spent three precious hours solving a non-existent problem. I guess gas fumes do have a long-term, detrimental effect on brain activity.