Fuel gauge on 1993 Dodge Dakota V8

Damaged float I expect.

Bad sending unit, bad ground, bad gauge, I have seen sending unit go bad they will work part way.

The fuel sending unit inside the tank just has an arm attached to a float which raises/lowers depending on fuel level. The tank itself will have internal dividers that help prevent sloshing of the fuel. There is no module to control sloshing

Check for a frayed wire touching metal and grounding out. The gauge works on resistance and it registering full indicates a short to ground. Either that or your gauge itself is bad.

your fuel system needs to be primed

FUEL SENDING UNIT IN THE FUEL TANK FAULTY.THE FLOAT ARM ATTACH TO SENDING UNIT.THE FUEL SENDING IS A RHEOSTAT WITH ELECTRICAL CURRENT FLOWING TO IT.YOU HAVE A COIL OF RESISTANCE WIRE IN RHEOSTAT.WHEN FLOAT+ ARM RISE WHEN PUMPING MORE FUEL IN TANK THIS CAUSE MORE CURRENT FLOW THROUGH COIL FROM RHEOSTAT TO FUEL GAUGE WHICH CAUSE FUEL GAUGE MOVE TO FULL MARK.WHEN FUEL LEVEL DROP THE FLOAT + ARM DROP CAUSE LOW CURRENT THROUGH RHEOSTAT COIL WIRE IN WHICH CAUSE FUEL GAUGE NEEDLE TO DROP SHOWING LOW FUEL LEVEL IN THE FUEL TANK.

It could be a bad fuel gauge in the dash unit, but....
Usually it's "The bad".
The fuel level sending wipe arm and windings on the fuel sender wear and send erratic readings.The only cure is a replacement fuel gauge sender.
The check engine light should not be related to the erratic fuel readings.
"The good".
If you have over 200,000kms or 120,000 miles on your van you need a new fuel pump anyway,so have a complete assembly put in which will have a new fuel sender on it.

The fuel sending unit is bad,it is in the tank,you may have to buy a fuel pump assy,to receive the sending unit ,if it is not available by itself.

check to make sure the wires are all connected at the sending unit,check to make sure you have a good ground.

This is a normal concern.
The instrument cluster uses 4 different operating modes to calculate the fuel level:
Anti-slosh (default mode)
Key OFF fueling
Key ON fueling
Recovery
After a fuel fill up, the time for the fuel gauge to move from empty (E) to full (F) ranges from 2 seconds to 55 minutes depending on which operating mode the fuel gauge is in.
The default fuel gauge mode is called the anti-slosh mode. To prevent fuel gauge changes from fuel slosh (gauge instability due to changes in fuel sender readings caused by fuel moving around in the tank), the fuel gauge takes approximately 55 minutes to go from empty (E) to full (F).
The key OFF fueling mode (2 seconds to read empty [E] to full [F]) requires 3 conditions be met:
The key must be in the OFF position throughout the entire refueling of the vehicle.
At least 15% of the vehicle's fuel capacity must be added to the fuel tank.
The instrument cluster must receive a valid key ON fuel sender reading within 1 second of the key being put into the RUN position. The key ON sample readings are considered valid if the fuel sender reading is between 15 ohms ± 2 ohms and 160 ohms ± 4 ohms.
If these conditions are not met, the fuel gauge stays in the anti-slosh mode, which results in a slow to read full (F) event.
The key ON fueling mode (approximately 90 seconds to read empty [E] to full [F]) requires 3 conditions be met:
The transmission is in PARK (P).
The key is in the RUN position.
At least 15% of the vehicle's fuel capacity must be added to the fuel tank.
In key ON fueling mode, a 30-second timer activates after the transmission is put into the PARK (P) position (automatic transmissions). When the 30-second time has elapsed and at least 15% of the vehicle's fuel capacity has been added, the fuel gauge response time is 90 seconds to read from empty (E) to full (F). When the transmission is shifted out of PARK (P), the fuel gauge strategy reverts to the anti-slosh mode. The key on refueling mode prevents slow to read full events from happening if the customer refuels the vehicle with the key in the RUN position.
Recovery mode is incorporated into the instrument cluster strategy to recover from a missing fuel level input during a refueling event. Missing fuel level inputs result from intermittent opens in the fuel sender or its circuits. Recovery mode (empty [E] to full [F] approximately 20 minutes) is initiated when the following 2 conditions are met:
The instrument cluster is in the anti-slosh (default) mode.
The actual fuel level in the tank is greater than what is being displayed by the fuel gauge