Did you check the connector a lot of them are not clicked into the housing properly & when fitted the pin pushes the socket back preventing contact try pushing down on the wire at the connector to see if it works
Can try that, they already sent me a 2 wire sensor and connector that I currently have on it, still doesn't work. I really have no clue why its not working, I ground the power wire from the gauge and the gauge sweeps, the ground wire it straight to battery. This is actually the third sensor I have tried for this gauge all from speedhut. Volts are 5v at the wire to the sensor.