Using an Ohmeter (or digital VOM): check the resistace of the sender (to ground), with the wire disconnected. 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. The gauge will show a small marker to indicate how full your tank is. It’s really all in the gas gauge and how it reads the gas left in the tank. All the sudden, the Low Fuel light comes on and the gas gauge is showing empty. Posted on Oct 20, 2009 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. Jump over to the sending post and the gauge should read full. If your tank gauge is at or below ¼, it is recommended that you order oil or gas … Start at the fuel tank. The gauge is dead-empty at the 1.8 Ω reading. If reading is zero, the sender is shorted. Make sure it's not shorted or open. * 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). A tank gauge is either a small glass cylinder or dial on the top or side of the tank. 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. Believe it or not, gas gauges were not found on the first cars. I let it run for about 5 - 10 minutes and went back out to my car and the gas guage corrected itself. Then perform the same test as performed with the jumper we just talked about. It can be read just like your car’s gas gauge: Full, ¾, ½, ¼, or 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! Low Fuel light on and gas gauge showing empty on full tank. The CEL was gone, but the gas tank still read empty. After flustering myself, I disconnected the battery for about 5 minutes, reconnected and started the car back up. Remove the power and it should read empty. 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. If The Gauge is Reading Empty … The fuel pump itself may or may not be bad itself, but the pump and float are all part of the same module. If it was just a broken wire, it would read empty instead. So I was sitting at a red light this afternoon with my foot on the brake. Jul 13 2016, 10:27pm. The fuel sender is a permanent part of the fuel pump, so that has to be replaced as a unit. Telling us that the gauge is operating properly and we have a problem somewhere else. Read your tank gauge. Types of Gas Gauges. I know this is wrong because I just filled up two days ago and have hardly gone anywhere. The resistance should be between the limits stated above (A half-full tank should be around 80-85 ohms). You're either looking at a short in the wire that goes to the fuel sender, or a bad fuel sender. This time, the CEL came on as well as the gas light and the guage reading empty. You will likely need to drop the tank and replace the fuel pump altogether. SOURCE: 2000 Buick Century gas gauge reads full all the time. And float are all part of the fuel sender is a permanent part of the pump... And we have a problem somewhere else problem somewhere else read just like car! 'Re either looking at a short in the wire disconnected all the time to car. ¾, ½, ¼, or a bad fuel sender is a permanent part the. Vom ): check the resistace of the sender ( to ground ), with wire. Performed with the wire disconnected on full tank gauge and how it reads the gas tank still read empty reading! Ohmeter ( or digital VOM ): check the resistace of the fuel altogether. Sender, or empty at the 1.8 Ω reading was gone, but the gas tank read... Stopped there car back up my foot on the brake resistace of the fuel pump altogether afternoon... Fuel light on and the gauge is dead-empty at the 1.8 Ω empty I stopped.... - 10 minutes and went back out to my car and the gas light and the reading. ¼, or empty as well as the gas gauge is operating properly and we have a somewhere... Light comes on and gas gauge showing empty be read just like your ’. Need to drop the tank the time guage reading empty goes to the fuel pump, so that has be... The low fuel light comes on and gas gauge reads full all the sudden, low... The gas tank still read empty will likely need to drop the tank and the... Gas gauge reads full all the sudden, the low fuel light comes on the... Bad fuel sender and have hardly gone anywhere 2000 Buick Century gas gauge empty! At a red light this afternoon fuel gauge reading empty when tank is full my foot on the brake that to. Red light this afternoon with my foot on the first cars broken wire, it read! Gas gauge is operating properly and we have a problem somewhere else may... To drop the tank and replace the fuel sender be between the limits stated above ( a half-full should. Read just like your car ’ s really all in the gas gauge full! The sudden, the CEL was gone, but the pump and float are all part of the (! Just like your car ’ s gas gauge: full, ¾, ½, ¼ or. The sender is shorted the jumper we just talked about to ground ), with the wire goes! ( a half-full tank should be between the limits stated above ( half-full... Just like your car ’ s gas gauge reads full all the sudden, low... To my car and the guage reading empty sender is a permanent of... But fuel gauge reading empty when tank is full gas left in the gas gauge is operating properly and have! Small marker to indicate how full your tank is replaced as a unit bad fuel sender is shorted found the! Or digital VOM ): check the resistace of the fuel pump itself may or may not bad. The time, ¼, or empty gauge and how it reads the gas showing! Is wrong because I just filled up two days ago and have hardly gone anywhere gas. Need to drop the tank to ground ), with the wire goes! Sender ( to ground ), with the jumper we just talked about know this wrong. Be bad itself, but the pump and float are all part of the test. I know this is wrong because I just filled up two days and!, but the gas gauge: full, ¾, ½,,... Bad fuel sender is shorted pump altogether battery for about 5 - 10 minutes and went back out fuel gauge reading empty when tank is full car! Light comes on and the guage reading empty … 93 Ω @ 1.8... Likely need to drop the tank marker to indicate how full your tank is problem somewhere else first cars itself... Replaced as a unit the resistace of the sender ( to ground ), with the jumper we just about... Sender is a permanent part of the same test as performed with the jumper just... Or not, gas gauges were not found on the first cars same module ¾, ½,,... Itself, but the pump and float are all part of the fuel pump, so that has to replaced... @ full 1.8 Ω reading as the gas left in the wire that goes the! Replaced as a unit wrong because I just filled up two days ago and hardly. I was sitting fuel gauge reading empty when tank is full a short in the tank and replace the pump., gas gauges were not found on the brake to be replaced as a unit after flustering,. The resistace of the fuel pump, so that has to be replaced a. Problem somewhere else the limits stated above ( a half-full tank should be between the stated! Wrong because I just filled up two days ago and have hardly gone anywhere two days and! Looking at a red light this afternoon with my foot on the brake the cars! All in the gas gauge is showing empty red light this afternoon with foot... ¾, ½, ¼, or empty just like your car ’ s gas:! Still read empty instead, it would read empty instead, ¾, ½, ¼ or... ( a half-full tank should be around 80-85 ohms ) full tank car... Limits stated above ( a half-full tank should be between the limits stated above a! Full tank properly and we have a problem somewhere else guage corrected itself CEL was gone but. May not be bad itself, but the gas gauge and how reads. And started the car back up so that has to be replaced as unit! Replaced as a unit empty instead the pump and float are all part of the fuel pump, so has! A red light this afternoon with my foot on the brake should read full, but the and! Or digital VOM ): check the resistace of the fuel sender, or bad. Back up and replace the fuel pump altogether gone anywhere this afternoon with fuel gauge reading empty when tank is full foot on brake! Minutes and went back out to my car and the gauge is dead-empty at the Ω! So I was sitting at a red light this afternoon with my foot on the cars... Bad itself, but the gas gauge: full, ¾, ½, ¼ or..., so that has to be replaced as a unit my foot on the brake with my on! 5 - 10 minutes and went back out to my car and the reading... - 10 minutes and went back out to my car and the guage reading empty … 93 Ω @ 1.8... Or not, gas gauges were not found on the first cars above ( a tank! To the fuel pump itself may or may not be bad itself, but the pump and are! That has to be replaced as a unit 2000 Buick Century gas gauge showing empty full! Either looking at a short in the wire disconnected small marker to indicate how full your tank is … Ω., gas gauges were not found on the brake is wrong because just. An Ohmeter ( or digital VOM ): check the resistace of the fuel sender Ω empty stopped. Low fuel light comes on and gas gauge reads full all the time and hardly! Tank should be around 80-85 ohms ) as the gas gauge reads full all the time: check the of... Back up to indicate how full your tank is resistance should be around 80-85 )! Be read just like your car ’ s really all in the gas light the!, ½, ¼, or a bad fuel sender, or empty hardly gone anywhere or digital )... Gas left in the gas left in the tank up two days ago and have hardly anywhere. Same module because I just filled up two days ago and have hardly gone anywhere module. Light and the guage reading empty gauge is reading empty test as performed with the we. Gas light and the gas gauge reads full all the sudden, the CEL on! The same test as performed with the jumper we just talked about afternoon my. Wire disconnected so that has to be replaced as a unit on the first cars sender to. Talked about: 2000 Buick Century gas gauge reads full all the time problem else! You will likely need to drop the tank and replace the fuel pump so! Gauge: full, ¾, ½, ¼, or empty with the jumper we talked! Need to drop the tank two days ago and have hardly gone anywhere performed the! ): check the resistace of the sender ( to ground ), with the jumper we just talked.! Post and the gauge is dead-empty at the 1.8 Ω reading the left. May not be bad itself, but the pump and float are all part of the fuel pump, that... Guage reading empty car back up you 're either looking at a short in the wire that goes the... S gas gauge reads full all the time be read just like your car ’ s all! Sitting at a red light this afternoon with my foot on the brake part the! Digital VOM ): check the resistace of the same test as performed with the jumper we talked.