My gas gage goes from having gas to showing empty for no apparent reason. The problem has gotten worse in the last few months

Does that model have a summer-winter setting somewhere near the air cleaner

The problem could be big and expensive mine solution is drive 300 km and fill up( 200 m. ) Presently I am doing.

Try un hooking battery.

The sensor in your gas tank needs to be replaced the good news is you can but just the sensor and NOT have to buy the entire unit.

their are quite a few reasons --needs tune-up--bad gas--throttle body clogging failing--cat converter failing--egr valve carboned up -fuel filter -these are a few

if the sending unit has been replaced and it works for a while then acts up again check the electrical plug and connections also look for a broken wire or nicks in the wires coating as corrosion inside the wire will cause a problem that circuit works by resistance not voltage

hi this sounds like it could be a couple of things, first the obvious have you checked the fuse? or it might be the relay in the fuse box might need replacing, and the fuel sender unit in the fuel tank, you also can check out the wires going to the sender unit, sometimes you can find these under the rear seat or in the boot/trunk area might be a simple case of one of the wires have come adrift there is a couple of things to check before having the sender unit replaced or the Gage..hope that helps

check your motor mounts

Sounds like you have a leaking head gasket.

on your last tune up you might have gotten some bad plugs i know they are new but sometimes they dont work straight out of the factory and your fuel guage connections are backwards