Fuel gauge has been flaky, especially when it gets below 1/2 tank.

It bounces up to full, some times settles back down, other times stays up towards full....

When I do fill the tank it goes to full and seems to read OK/normal until it gets about 1/2 tank


Any ideas ?

No doubt on this one. The fuel pump needs a new level sensor. There are small metal fingers that move with the float arm across a metal grid on a printed circuit board that will indicate the fuel level. Those fingers wear and you get inconsistent readings. Very common failure. You can purchase the level sensor separate from the pump. Not sure on the LeSabre, but my Bonneville had an oval shaped access panel in the trunk to get to the fuel pump allowing you to change the sensor in well under an hour. Without the access panel you have to drop the tank.

Or, just keep track of the miles you drove since the last time you filled up with gas.

Screw the sensor. That car is 13 years old. Surely that pump is on the way out also. Replace the whole sending unit with an AC Delco. Stay away from Airtex no matter what.

I'd replace the whole unit as well, especially if you do not have a trunk access hole to get to the unit.

If you do have the access hole in the trunk, and money is really tight during the Holidays, then you could just replace the level sensor, but if you go that route I'd consider replacing the pump ASAP.

I had same problem on my 2002 Lasabre. Had to have the sensor in the tank replaced.