Jul 13 2016, 10:27pm. A tank gauge is either a small glass cylinder or dial on the top or side of the tank. It can be read just like your car’s gas gauge: Full, ¾, ½, ¼, or empty. Remove the power and it should read empty. The CEL was gone, but the gas tank still read empty. 93 Ω @ full 1.8 Ω empty I stopped there. All Activity; Home ; Fullsize Truck & SUV - 1999-2006 GMT800 & 2007-2013 GMT900 Platforms ; 1999-2013 Silverado & Sierra 1500 ; Fuel Tank Full...fuel Gauge Reading Empty! After flustering myself, I disconnected the battery for about 5 minutes, reconnected and started the car back up. You will likely need to drop the tank and replace the fuel pump altogether. If The Gauge is Reading Empty … The fuel sender is a permanent part of the fuel pump, so that has to be replaced as a unit. After hooking up the unit under the car for testings, it moved the gauge smoothly from E to F. With the float arm approximately .125" from the empty stop, the unit was reading 3.5 Ω and the gauge was about a needle's width from the 'E' line. SOURCE: 2000 Buick Century gas gauge reads full all the time. If your tank gauge is at or below ¼, it is recommended that you order oil or gas … Types of Gas Gauges. Jump over to the sending post and the gauge should read full. Make sure it's not shorted or open. Understanding how the gauge works and how to read the real level of gas in your tank can help you drive the farthest you can, even when the tank says empty. * fuel float full of fuel (very common) * blown F1 fuse on circuit board (very common) * bad connector on the sending unit plug (rare) * bad guage (possible) Once the repair was completed, I was able to obtain an OHM reading of 0.01 - 88.8 (empty-full). Then perform the same test as performed with the jumper we just talked about. Low Fuel light on and gas gauge showing empty on full tank. The gauge is dead-empty at the 1.8 Ω reading. I recommend having a certified technician, such as one from YourMechanic, determine the exact source of the fuel misreading and replace the fuel pump if needed. Telling us that the gauge is operating properly and we have a problem somewhere else. So I was sitting at a red light this afternoon with my foot on the brake. I let it run for about 5 - 10 minutes and went back out to my car and the gas guage corrected itself. I know this is wrong because I just filled up two days ago and have hardly gone anywhere. If it was just a broken wire, it would read empty instead. The gauge will show a small marker to indicate how full your tank is. This time, the CEL came on as well as the gas light and the guage reading empty. Posted on Oct 20, 2009 Start at the fuel tank. Believe it or not, gas gauges were not found on the first cars. If reading is zero, the sender is shorted. When the tank is full, the resistance decreases, causing more current to flow to the gauge, which moves it "up," or toward the FULL indicator. Read your tank gauge. The resistance should be between the limits stated above (A half-full tank should be around 80-85 ohms). It’s really all in the gas gauge and how it reads the gas left in the tank. The fuel pump itself may or may not be bad itself, but the pump and float are all part of the same module. All the sudden, the Low Fuel light comes on and the gas gauge is showing empty. Using an Ohmeter (or digital VOM): check the resistace of the sender (to ground), with the wire disconnected. You're either looking at a short in the wire that goes to the fuel sender, or a bad fuel sender.