My 1996 ford taurus gas gauge dosen't work right! when you fill the tank up! the gauge only goes to 1/2 tank then drops back to empty.... Never says how much gas is in the tank! Fuel pump works great!!! what do I do Joe....

That's best left to the professionals unless you're real handy with tools and have a garage to pull the car into. Sometimes the ground wire on the fuel gauge sending unit goes bad and has to be re-grounded, Most of the time, I have found the level float on the fuel pump assembly goes bad and the whole thing has to be removed from the gas tank. If you're lucky, there is an access panel through the trunk or underneath the back seats so the fuel pump can be removed. If your car doesn't have these then you'll have to drop the gas tank to remove the pump assembly. Obviously either way, run the gas tank down close to empty before attempting to remove the pump assembly, and no smoking open flames and try not to cause sparks when using wrenches or other tools...wouldn't want you going BOOM!!!

If could be a loose ground or the fuel level arm in the tank has a loose connection or is going bad.

One of the wires to the sensor is touching a ground. It may be getting pinched

change the fuel filter for one, this is telling you that your pick up in the tank is getting clogged, I would drop my tank, and drain it, flush it, and check the pump at that time

Fuel level sending unit. that is the most common problem with these vehicles that cause the gauge to quit working

It sounds like the fuel sender is bad in the fuel tank.

sending unit in tank needs to be replced, drop down tank and replce

I am very familiar with this problem, u will need to replace the gas gauge sending unit in the fuel tank.

i know that if the gas cap is loose then the check engine light will come on. as far as the fuel gauge going up and down the "float" you have in your tank could be getting stuck. This is a pain in the rear to change because you will have to drop the fuel tank and either replace the part connected (best bet) to it or make sure the passage is clear.

id say either your sender unit is nackered or you have a bad earth to the body