My gas gauge needle won't move after i filled it up

If your fuel gauge is showing you in accurate readings this is normal to all vehicles that are not used to fill-up gas full regularly but sometimes the cause of the inacuracy is due to faulty float valve in the gas tank you need to replace it

If it is showing that it is empty, the float may have sank. However, the cause could be the gauge in the dash or the sender and the sender is in the tank. It is not easy to change because you have to drop the tank. It is cheaper to replace the sender than it is to change the dash because the dash guages are all on one unit. However there are tests that can be run to see what the issue is and the tests are done using meters and jumpers etc to see if the guage responds to those. Then they know whether it is the sender or the guage.

Sounds like your sending unit could be bad.

It may be the sending unit in the tank that needs replacing. Here's how you can check: Turn the key on and disconnect the sender unit at the gas tank. Ground the sender unit's wire with a jumper wire from the truck's harness to ground. Watch the gauge. If the gauge on the dash is good, grounding the sender wire will cause the gauge needle to react and should move to full. This would indicate a new sending unit is required. If the gauge doesn't move when the sender unit is grounded, the gauge is bad and needs replacing. Pull the instrument cluster out to replace the gas gauge. Likely any old ford gas gauge might work-back then, there were not so many production changes.

The sending unit in gas tank is broken - hence the wrong readings of how much gas is in the tank. Replace unit.

I would drive at least 100-150 miles before I made any judgements about the gauge or the fuel mileage.

Your tank is 19 gallons and you get about 18 miles combined miles per gallon. Thats city and highway. Highway is around 21 and city is about 16.

the fuel gauge sending unit in the gas tank is a mechanical part, but you may have an electrical problem. the needle is moved by an electrical signal. you can check the wires coming out of the back of the gauge, one will run to a chassis ground. make sure that wire has a good connection to ground, first because it won't work right without it and second because it's lots easier than the next thing you will have to do if that doesn't make an improvement. if you see no difference after checking the ground then you need to drop the tank and replace the fuel level sending unit. you will have to remove the fuel pump to get to it so you might want to replace it while you have it out, that's your call. your vehicle is new enough that the decision would be more based on miles than age. hope that helps

Fuel gauge sending unit in the gas tank needs replacing.

If you remove the sending unit in the gas tank, move it manually by hand as u saw done earlier, the gauge on the dash should also move. As long as the sending unit in the tank isn't 'stuck' at the half full level, the gauge should register empty to full as it moves. To be honest, I'm not sure if I would bother taking the sending unit out. 1st, u must be very careful not to blow yourself up when working on the gas tank (no sparks, etc), all u really need to do is fill up your car, see how many miles a tank of gas will go (carry a can of gas with u to see how many miles before u run out). If it's 350 miles, just set the trip gauge to zero every time u fill up, and get gas every 300 miles so u don't run out. If the sending unit moves freely, everything (wiring ) is connected properly, then it probably is the fuel gauge. good luck!