Gas problem when my gauge reach a half a tank it act like if its staving for gas runs poor. i put a couple of gallons in then it runs ok.

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

did you plug it into laptop to check if sensors is right?

replace front fuel pump because gauge is made into fuel pump and not serviceable. Or poor boy way of getting by would be fill front tank with gas reset mileage drive normal for a day. refill again with gas note gallons used and mileage driven for average miles per gallon. front tank should be around 17 gallons multiply by mile per gallon you figured

Just a question. Do you run your car on empty. If so that could be your problem with an empty tank you are sucking all the dirt through the filter and making it plug up. It is better to keep your tank above half full and does not cost any more than to run on empty. All mechanics will tell you to always keep your tank above half full.

from what you are describing you have two(2) different problems
1- the wacky gauge- its acting like a grounding issue- wires are crushed/smashed on tank connector
2- not filling - venting issue- vent line to top of tank pinched
3 solution- run tank down to 1/4 or less and DROP tank down to inspect wires and hoses- sounds like at some point in time the tank took a hit and wedged itself upwards against the underside,pinched the vent line so there is too much pressure in tank and also crushing the wires/plug causing the erratic readings(worse with less weight as the tank moves more)
if unsure of how to do this- you can get a manual such as a HAYES book at auto parts story- good luck

yes they are similar. you would have to pull the tank out to fix this problem

Hi There. Let's see if we can help. If truck runs normally after filling the tank, next time it acts up and you add fuel, record how much fuel you added. You then need to determine how many gallons your tank holds. A quick phone call to your local Dodge dealers parts dept with the VIN number will usually get you that info. Next, refering back to your notes, if you have a 20 gallon tank, it acted up at 1/4 full, then you should have added approx 15 gallons! This simple test verifies that the fuel gauge is reporting fuel level correctly. If it is, then there is most probably an issue with the fuel pick-up tube or fuel pump strainer in the tank not extending to the bottom of the tank. Inspect the exterior bottom of the tank. Are there indications of damage to outside bottom of tank? Is it pushed up or deformed? Fuel tanks, especially on pickups, are prone to damage from running over something. If no visible damage is apparent, have you had the fuel pump replaced or did the problem arise after the fuel pump assembly was replaced?. Summary: If fuel gauge reads right and no visible damage to tank is apparent, then the tank needs to come down for removal and inspection of the fuel pump module. Good Luck!

The 99 expedition comes with a 26 gal tank as standard equip. and there is an optional 30 gal available. I suspect the gas pump you used is not accurate, and needs to be recalibrated. I think it's just a coincidence that the gauge is acting up now. Hopefully I'm wrong, and by some miracle you actually are now getting 300 miles on a half tank of gas! You may have a bad sending unit, this would result in inaccurate fuel tank readings.

I also have a 04 with a 1.8L. same problem. I took the fuel regulator off. It is a black box behind the rear tire under car. It only has 2 bolts to take off. After that there is a couple of vent hoses from the tank going to this box. Unplug them and 1 electrical connection. The electrical connection and one vent is connected to a T connection on the box that you can unplug by twisting on the T. Take that T off and look inside where you unplugged the hose on this T. There is a spring and a little plunger inside this tube. The plunger gets stuck. I took a little screw driver and some PB blaster and worked that plunger back and forth a couple dozen times and it unfroze. Put it back together gassed up just fine. I did not look but I was told regulator can be replaced for 200$. But a can of blaster is cheaper.

Ok ready for this one,new gas cap,its true cars with bad gas caps will cause the check engine light go on,or your problem,it has to be pressurized when full and no air in the tank its ok,but as you use gas and have air in the tank with the low fuel the air pressure is leaking pass the cap,thus losing pressure,too bad you had to fix all the other stuff but look at it as an investment,after this works please give me a fix ya thanks