LED fuel gauge not reading proper fuel level on 2005 Night train

The fuel level sender is located on the fuel pump hanger assembly. Sometimes the fuel pump, sender and hanger are all individually serviceable while other times the whole unit is replaced as a module assembly. The fuel level sender works by taking a 5 volt reference signal sent by the powertrain control module (PCM), modifying the voltage using resistance based on fuel level, then sending that signal back to the PCM. The PCM then reports the information to the body control module (BCM) so that the fuel level gauge in the instrument cluster can be adjusted accordingly. Fuel level senders are the most common failure for inaccurate fuel gauge readings. When the sender (or module assembly) is replaced, it's important to ensure the float is properly attached to the sender arm otherwise the resistance will not change with fuel level as designed. If this was done properly then there is likely a problem with the gauge or in the circuit between the level sender and the PCM. One easy way to test the circuit and gauge is to unplug the fuel pump; this creates an infinitely high resistance which should bottom out the gauge. Then, a jumper wire can be used to short the two sender wires (the smaller 2 of the 4 wires) to create a zero-resistance circuit which should top out the gauge. You can read more here: https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-fuel-gauge-sender

These are two different issues, cam sensor has noting to do with your fuel level unit.

are all the wires in properly ?

fuel sending unit

You have a defective sending unit, it's in the gas tank, tank will have to be remove to replace.

Sorry to say,but the fuel sending unit is the problem,the fuel tank will have to be lowered out of the vehicle to replace the unit.If the fuel sending unit is not available by itself you will have to replace the whole fuel pump assembley.

The gauge circuit is shunted on most cars, this is wierd, but needed to stabilize the readings... Your description sounds like normal function. Drivers would complain if the qauge were to be instant, going around corners, starting, stopping, all move fuel, and the gauge would indicate this, cauing driver alarm...Been this way for ever, although yours sounds like it is on the far side of the scale...if it reads correctly after a while, you could replace everything and you would have the same performance.

Most likely fuel level sensor in tank.

check this link out' it might help you: http://www.hdtalking.com/self-help-2003-night-train-fuel-gauge-wiring-instructions-preview.htm