How do i replace gas filler door on a 2005 malibu. the square type

you open the fill door and you smell gas?

is the check engine light on?

is the filler tube rusted?

have you tried a new fuel cap from the GM deal (do not use aftermarket caps from your local parts store)?

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

In my wife's case it was that the neck of the filler (where it contacts the gas cap) rusted. It didn't allow a good seal. Since it was a 2005 we also replaced the gas cap in 2013.

if you have auto daytime lights and they don't work then your radio will not work either. trust me on that. you have one lead to 12v source and acc lead that is wired to auto daytime lights which when you open your door radio shuts off.

A lot of cars had a pull in the trunk or somewhere close to the filler door just for this purpose, look around or check the manual for the pull, It is usually bright yellow and marked fuel filler, check it out, hope this helps.

To fix this, you have to drop the gas tank to access it. You will want to run it low on gas so it's not as heavy to deal with. Then depressurize the fuel system by removing the fuel pump relay, and starting the car. It should run for a second and die. Take the straps loose that hold the tank up, and lower it enough that you can access the filler neck and overflow hoses to take them off. Lower the tank enough that you can disconnect the fuel lines and the connectors for the fuel level and fuel pump. You should then be able to pull the tank out. If your car has around 100,000 miles, or more, you may want to replace the pump at this point while you're at it. If you get a new pump, it comes with a new sender as well, and since you're doing the same thing for both, it makes one less trip into the tank. You will have to remove the locking ring, which requires a punch and a hammer to remove. The pump and sender will then lift out. You can then remove the sender from the pump at this point, and put everything back together. You will probably want to empty any remaining gas into gas cans so it's not as heavy going back up.

most likely the fuel sending unit,within the fuel pump assembly within the tank....theres a replaceable printed circuit card within the tank which always gets dirty\worn out and contaminated....its very common on malibu's Cavaliers,sunfires etc...tank has to be lowered to replace it

1- remove fuel from tank, 2- take and loosen the tank straps, lower tank down far enough to disconnect the wiring and fuel lines.then lower tank to the ground. you may have to loosen the screws for the filler neck hose, inside of filler door to remove filler hose from tank. take off lock ring on fuel pump and pull pump out of tank, be carefull you may have to wiggle it out of tank as not to harm filter unless changing it. before starting on tank. disconnect battery as not to get any sparks. to install is reverse of removal.

The tank vent pipe may be blocked or kinked, it usually branches off the main tank filler pipe and can be seen from under the car.

check ruber hose from gas filler to tank.hose clamp
loose or hose have a hole in it.

There was a recall on this type of problem a while back. I had the same issue and brought it to Dodge to get fixed. You should have received something in the mail but if you didn't here is the information.
Make: DODGE Model: DURANGO Model Year: 2005 Manufacturer: DAIMLERCHRYSLER CORPORATION Mfr's Report Date: FEB 01, 2005 NHTSA CAMPAIGN ID Number: 05V034000 N/A NHTSA Action Number: N/A Component: FUEL SYSTEM, GASOLINE:STORAGE:TANK ASSEMBLY:FILLER PIPE AND CAP Potential Number of Units Affected: 26000 Summary:
ON CERTAIN SPORT UTILITY VEHICLES, THE FUEL TANK FILLER TUBE INLET CHECK VALVE MAY NOT FULLY CLOSE AT THE END OF REFUELING. THIS COULD ALLOW SOME FUEL TO ESCAPE FROM THE VEHICLE FILLER NECK. Consequence:
FUEL LEAKAGE IN THE PRESENCE OF AN IGNITION SOURCE CAN RESULT IN A FIRE. Remedy:
DEALERS WILL INSPECT THE INLET CHECK VALVES AND REPLACE THE FUEL TANK ASSEMBLY FREE OF CHARGE. THE RECALL BEGAN ON APRIL 4, 2005. OWNERS MAY CONTACT DAIMLERCHRYSLER AT 1-800-853-1403. Notes:
DAIMLERCHRYSLER RECALL NO. E01. CUSTOMERS MAY ALSO CONTACT THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION'S VEHICLE SAFETY HOTLINE AT 1-888-327-4236 (TTY 1-800-424-9153), OR GO TO HTTP://WWW.SAFERCAR.GOV.