I checked my other sending unit today. Grounded the sending unit hooked up the connector. Went through the full range of motion on the sender arm and could get occasional readings if I wiggled the sending unit arm. Gauge works but sporadically. Decided to go fill the tank completely ( I have been sitting slightly above half a tank) to see if I could get a reading. Three gallons added, reading still on empty. 4 more gallons filled the tank, reading is now at 3/4 full. I am only reading the last 3 gallons of the tank. This is a brand new classic industries gauge that ohms out perfectly when out of the tank. Anything that might cause this other than a defective sending unit? Gauge, wiring, ground IVR?
