Gas gauge problems....the hell is going on?

So a couple weeks ago my guess gauge starting acting weird. It would be in random spots all over the gauge, Say 1/4 tanks for a drive, than get back in and I got 3/4 tank. I even filled up and it only showed half tank, drove about 30 miles and wound up with a little more than half a tank.
Next in the morning it was showing empty, and in the afternoons it would work again. But sometimes it pegs empty as far as it will go. Other times just around the Empty mark.
Now that the weather isn't warming up, the gauge isn't going up.
I did drop the tank when the weather was warmer about a week ago and cleaned the connections which were a little corroded and rusty and everything was working that night. Next morning, back to E....
Any ideas?
this is on a 62 impala by the way.

 

how old is the sender. it sounds like it's toast

 

Bad ground ,sender, or maybe float sinking (if it has a brass one).

 

This was the first time in my 12 years of owning the car that I've ever dropped the tank. I didn't pull the float out because its my daily and I had to work the next day (something would have surely broke if I did)
So as far as I know everything is original. It's probably all of the above.....

 

It's probably a bad ground, check that first. Run a fresh ground from sender to a clean spot on the frame.
If that doesn't help, jump the sender wire to ground and see if the gauge holds steady at either full or empty. If it does, that proves out that side of the circuit. (meaning your gauge is probably fine).

 

Ok, to help more please explain what you did prior to having the problems. Did you pull the tank before having problems, or after? I agree, it's probably an electrical problem. Find what the resistance of the sender should be and check with an ohm meter to make sure it matches. Double check your grounds. Check for pinched or damaged wiring, etc.

 

what messed up is that i bought a new murano . and its doing the same shit ..... i hate new cars

 

If your sender float doesn't float (on top) it tends to just drift around in the waves giving you random readings.

 

This problem was out of the blue. I dropped the tank after the problem started. Last night driving home I reached behind the gauge, while driving., and fiddled with some wire and the qauge went from pegged empty to empty. Not sure what that means. Might try and work on it some today. Really don't feel like pulling that tank again.

 

ETHANOL is killing the sending units.

I would just go ahead and buy a new sending unit ... drop the tank and install the new unit.

 

So I worked till one today, drove 30 minutes home and nothing working. Stopped at the grocery store for 30 minutes, parked in the sun, came back out and it's working......clueless.

 

i have this problem on my willys. after lots of testing i figured out that there are some electrial components that are bad and need to be replaced. my spedo, fuel, and something else were built into 1 cluster and that cluster is bad. Basically my fuel guage was reading like my voltage guage.

 

I had a am 3 series bmw that was like that, however, on my impala they are all seperate....sadly the speedo doesn't work either.

 

in case anyone was wondering, it was the brass float that was bad. It was half filled with fuel. Not sure why the temperature affected it so much, but it did.

 

That's what I figured. Ground issues usually don't present themselves like that, random readings. Bad grounds or senders typically read full at 1/4 tank, etc.