Fuel gauge either on FULL or EMPTY

Hello! The FUEL gauge in my 2004 Chevy Malibu is not functioning correctly. It is generally either on FULL or on EMPTY, but never on any level in between. Previously, when I would fill up the tank, the needle would drop to EMPTY, but after about 40 miles or so the needle would return to ALMOST full and proceed to track fuel correctly. However, now the needle simply sits on either F or E, with no in between - as you can imagine, this has resulted in running out of fuel a few times. Any suggestions as to how to troubleshoot this issue? Thanks!

Seems to me that the float in the tank isnt doing what its supposed to do. So which means dropping the tank and replacing the whole pump assembly. But I have heard of these cases before and what my buddy did was reset his trip meter after putting 20 dollars in and could calculate milage with how many gallons...He did that twice and it corrected it self.....Bad gas can have that effect on somethings. Let me know your turn out.

what do you mean by "reset the trip meter"?

there is a service bulletin regarding a vent hose inside the tank interfering with the sending unit float movement.

bad sending unit potentiometer contacts is another issue.

both require removing the sending unit from the tank. so if external wiring is ok you probably will have to drop the tank.

The " trip meter " is the odometer .

Some of the '04s require total fuel tank replacement. That problem is widespread on Maxxes (such as mine - my fuel tank was replaced in '04), but some sedans have the problem as well. Most of these issues cropped up before '06; I'm surprised to be hearing about this again 4-5 years later.