Replaced a fuel module but the fuel gauge still reads empty when I know I have a full tank.

Previous owner changed complete fuel maudule it has a faulty fuel needle on dash when I baught it , so I completely changed the fuel maudule, still fuel needle reads empty where as I know I have a half tank

My car has 189790 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
This may be related to the fuel sending unit in the fuel tank. Your fuel tank has a float type unit that sits inside of it which monitors the fuel level in the tank and transmits this information to the ECU, which then allows this to be displayed in your fuel gauge in the dash. When the sending unit in the tank is not working properly, this will cause inaccurate readings to be displayed as you have noticed. If you need some assistance with getting this fixed, I would recommend having an expert from YourMechanic come to your home to diagnose and replace your fuel tank sending unit as necessary.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Fuel gauge stuck on full

A faulty fuel gauge resistor can send a bad signal to the instrument cluster which can cause the gauge to permanently read full. This is an issue, as the driver needs to know the accurate fuel level of the vehicle as to not run out of fuel.

Depending on the level of electrical resistance, the fuel gauge changes to reflect the level of gas in the tank. In the event that the fuel gauge constantly reads empty, full, or some random nonsensical reading, then there is an issue with the fuel gauge, the sender, or the wiring in between.
How do I reset my Chevy fuel gauge? There are two ways to reset your Chevy fuel gauge. For newer vehicles equipped with the instrument panel cluster, simply push and hold the button on the end of the turn signal lever for about 10 seconds. You can also try disconnecting the positive battery cable for about 10 seconds.
If the internal circuits are shorted, they may peg to FULL or EMPTY. If the circuit is open, the gas gauge will likely sit at EMPTY and never move. Instrument Cluster Failure is the least common, and likely the most expensive problem to fix.
Press and hold the “Trip/Odo” button and turn the car back on. While you`re holding the button, turn the key back to the “ON” position. Hold the button down for another 2 seconds after the car`s back on, then release.
Ray: Actually, you probably just have a faulty gas tank sending unit. There`s a float in your gas tank that floats down as the fuel level drops. As the float goes down, the metal contact attached to it slides down a variable resistor. And the contact`s point on that resistor tells your gas gauge how much fuel is left.
The instrument cluster fuse, also known as the dashboard fuse, powers the gauges and displays on your vehicle`s dashboard. This includes the speedometer, tachometer, fuel gauge, and temperature gauge.
If your vehicle has an electric fuel pump, you can use a fuel system cleaner to clear any sediment buildup or blockage. If you have a manual one (usually found in older model vehicles), you can actually open the pump to clear debris out of its internal filter, though that isn`t an option in most modern vehicles.
If the dash gauge needle fails t move, the dash gauge is defective. If the gas gauge works, but reads lower than it should, check for defective wiring between the gas gauge and the tank sending unit. Also check for a poor ground at dash gauge and the sending unit by using a jumper wire.
If your vehicle has an electric fuel pump, you can use a fuel system cleaner to clear any sediment buildup or blockage. If you have a manual one (usually found in older model vehicles), you can actually open the pump to clear debris out of its internal filter, though that isn`t an option in most modern vehicles.
It can interfere with the vehicle`s fuel injection system, resulting in decreased power and acceleration. Overfilling your gas tank can have serious consequences, both for the environment and for your safety. Not only can it cause environmental damage, but it can also lead to a potential fire or explosion.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Replaced a fuel module but the fuel gauge still reads empty when I know I have a full tank.
ANSWER : This may be related to the fuel sending unit in the fuel tank. Your fuel tank has a float type unit that sits inside of it which monitors the fuel level in the tank and transmits this information to the ECU, which then allows this to be displayed in your fuel gauge in the dash. When the sending unit in the tank is not working properly, this will cause inaccurate readings to be displayed as you have noticed. If you need some assistance with getting this fixed, I would recommend having an expert from YourMechanic come to your home to diagnose and replace your fuel tank sending unit as necessary.

I have a 1981 e-350 with dual fuel tanks the p.o. added a third tank and 3 electric fuel pumps along with sepparate gauges and swi
ANSWER : The switch you are referring to is vended with the required electrical and fuel schematic (I just looked in the box) that answers your installation question. If you want an advance view, here is a link as well. Yes, you need a return line and just refer to the aforementioned link. If you are retrofitting back to OEM, I strongly encourage you to buy the original Factory Service Manual (FSM). There are lots of details attending this system and obviously it is difficult to recount it all here. The FSM will make your life much easier and you can then make sure your installation is perfect. Alternatively, YourMechanic can dispatch a certified mechanic and perform the whole retrofit and check out if you desire. Just request and schedule a generic service such as fuel pump service and the mechanic will come to your location and estimate the parts and labor required. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Can 1 man replace a fuel pump and sending unit, clean out sludge and particles from fuel tank in about 1 hour? Think I was scammed
ANSWER : To drop the fuel tank on your model, and immediately re-install the tank (without any cleaning or service) would require about 2 to 3 hours in total for an experienced professional if a lift is available. The fuel pump itself can be installed without removing the tank but to do that you must have access to the inside of the car because the pump is removed through an access panel under the rear seat. Also, you can’t drop the tank without access to the inside of the car because to drop the tank the wiring harness has to be disconnected and that connection is only accessible from inside the car. So, if the car was locked, obviously no work was performed on the vehicle. YourMechanic does offer these services and you can start by requesting fuel pump replacement. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

1996 F150 4.9 5 speed. Frt. Fuel pump quit working. Put fuel in rear tank and it sucked the fuel to the frt tank.
ANSWER : The two tanks are designed to work together and so BOTH pumps must be functioning and, as well, the related fuel system supply code, the Code P0232 that has set has to be resolved. P0232 means that the fuel pump relay is stuck on, keeping power supplied to the fuel pump even after the ignition has been turned off although another possibility is the fuel pump secondary power circuit has a short to battery voltage. The factory service manual (FSM) specifies a very lengthy diagnostic (because you have separate tanks). If you do not have the FSM, your best bet is to request a fuel pump diagnostic – dual tanks and let a certified mechanic get to the bottom of this. With regard to the other code, P0704, that code will set if the clutch switch is defective, there is worn clutch pedal lever or clutch lever bushing, shorted or open wiring and/or connectors in the clutch switch circuit, a blown fuse or burnt fusible link and/or, rarely, a faulty PCM or programming error. If you request the pump diagnostic the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

I have a 1999 ford taurus ohs the fuel pump was replaced about two weeks ago at that time the fuel gauge reads as if it is empty e
ANSWER : Hello, thank you for writing in. The first indication that something is wrong is that the fuel level sending unit was not reading. If the pump was brand new, then it was bad to begin with. The fuel float is attached to the fuel pump, and the entire unit is often referred to as the "fuel module". Now that there are signs the fuel pump too has failed, you most likely need to install an entire new unit. Do a quick test to see if the pump is trying to work at all by turning the key to the "On" position. Listen for the pump to prime (a faint buzzing). If you do not hear it, the pump is not working at all. For help resolving the issue, contact our service department to schedule an appointment.

Fuel gauge and tank not holding enough
ANSWER : The most common problem is the fuel pump sending unit is bad in the fuel tank. The fuel gauge may also be bad in the dash. The best and quickest way to test the gauge is to disconnect the connection at the fuel pump and see if the fuel gauge moves when you turn on the key. If you see some gauge movement then the fuel pump and sender will need to be removed and the sending unit tested. Sometimes the sender gets caught when the fuel tank inside slosh panel is out of position and binds the sender holding it all the way empty. You would need to check all this when the fuel tank pump and sender is removed. If you need a mechanic like one from YourMechanic to come to you and remove the fuel pump and sender to test the sender operation, then just set an appointment for a mechanic to come to you.

Just had cluster replaced on a 2005 Ford freestyle. Filled up tank and a day later was driving car fuel tank light came on
ANSWER : Hi there. The only mechanical item that might cause the fuel gauge to act this way would be some malfunction within the EVAP vent solenoid system. However, if this occurred right after replacing the instrument cluster, it’s more likely due to an electrical fault that occurred during the installation. I would contact the company or mechanic that completed the instrument cluster installation to ask them if they can take a look at this issue, as it is likely an installation fault and not mechanical.

My new gas gauge should read from about 10 o’clock for empty and about 2 o’clock for full. My needle goes to about 5 o’clock.
ANSWER : You would need to see if the sending unit is shorted to ground. If you test it with an ohm meter you should get somewhere between the 5 and 30 ohms. If you are getting 5, then the gauge will be at full; and if you get 30, it should be at empty. If you are reading too low on ohms, then you have a shorted sender. If you’d like some help looking at this, a technician from YourMechanic can come to your car’s location to inspect your electrical system in person and let you know how to best proceed.