fuel guage stays on full all time, replaced fuel pump assembly, no fuses blown?

Answer 1

replace fuel gauge

Answer 2

You should take your vehicle to a mechanic. It could be a number of problems, and it depends on the year/make/model of your vehicle. It could be a grounding issue in your wiring harness, the gauge itself may be broken...

You say you've replaced the fuel pump assembly. By that, do you mean the unit you replaced was a pump/sending unit combo? Some vehicles have a separate pump and sending unit, while others have a piece that is a combination of the two.

Take it to a repair shop. If it comes down to an electrical problem in the wiring harness you most likely will not have the tools and/or know-how to do it. I don't mean that to be insulting, I'm just saying it is a very involved process. Until you can take it in, simply reset your odometer every time you fill up on gas (fill up every time). If you know your vehicle can go 400 miles on a full tank of gas drive until you hit 350-375.

Also, be prepared for the expense.

Answer 3

it would depend on the type of car, as different cars have different ways of determining the amount of fuel, old vw beetles for instance have a steel cable attached to the float, and it is done by the use of that.

the sensor inside the fuel tank may be seized, or faulty, best way to find out it to remove it from the tank, and put a multi meter across it, to check the resistance of it, it should change as you move the float up and down, if it doesn't then there Your problem, then U remove the electric contacts from the tank, lot at the fuel guage and see if it moves, if not ground the wire to the car body, if it still does not move then id say it the guage in the dash that is broken, or seized

i hope this helps

ps DON'T ground the wire to the car body near the fuel tank, or on the fuel tank, as the spark may cause an explosion

Answer 4

Two possible solutions.

One the sender unit is defective, and or ...
Two, the wire supplying power to the gauge has an electrical short in it.

An electrical short will keep the contact open, and the gauge reading full.

Also depends on what kind of car, GM and Oldsmobile had a problem with their sensors in the late 1990's early 2000's that caused sensors to show full until the gas tank was almost empty, and then within a few minutes, it rapidly registered zero... (not much fun if it is 25 miles to the next gas station (40km for you metric people)

Answer 5

Replacing your fuel pump will not fix the problem. The float might be stuck, located in your fuel tank and very expensive to fix. It might be the gage itself, but I would not worry about it, especially if it is an old car. All you need to do is fill the tank up and restart your odometer to zero. Set it every 200 miles after every fill up. Keep doing this and don't forget to rest it every time you fill up. Now you can take the 400 dollars that it would take to fix the problem and do something worthwhile with it....KECK

Answer 6

You Replace the whole Fuel Tank Sending Unit??
if so it's your Fuel Gauge on the dash not easy to fix sorry

Answer 7

There are two possibilities.
1] The fuel sensor from the tank to the gauge is bad (moost likely cause) or..
2] Bad fuel gauge

Answer 8

check the wire from the gauge to the sending unit for being grounded out somewhere, grounding that wire out will make the gauge resistance low which makes the needle go to full, high resistance makes the needle go to empty, thats in fact what the reostat inside the tank does to make a gas gauge work. if you find out which wire it is using a shop manual, trace it back to the tank or cut it and run a new gauge wire temporary to test it .

Answer 9

If you would include what kind of vechile it is with your question you might get better answer.
GM,FORD & CHRYSLER gauges all work different from one another.
Unhook a GM gauge wire from tank and gauge will read full.
Unhook a Ford or Chrysler gauge wire from tank and the gage will rrad empty.
Could be a grounded or open curcit depending
on car.

Answer 10

Bad Guage!

Answer 11

Fuel sender