Need fuel gauge help

[CJDan]

My fuel gauge is not working correctly. I have tried many things, i have replaced the fuel gauge 3 times and the fuel sending unit 2 times. Currently right now the fuel gauge will go all the way just past full and then a few minutes later is will go to empty again. The ground is working perfectly on the sending unit. Does it have something to do with the ohms between the sending unit and the fuel gauge? Any input you guys have let me know. Btw its a 15 gallon fueltank

 

[SteelHeadz]

Process of elimination. Run a temporary ground strap to the sender. If the issue is still evident, run a signal wire from the sending unit to the gauge. With a new gauge and sending unit, i would think that the issue is in the wiring. If the signal wire grounds intermittently, the gauge should read full, if the signal wire has an intermittent open short, then the gauge should read empty. I'm assuming you replaced the gauge with the factory spec. unit as well as the sending unit.

 

[CJDan]

Process of elimination. Run a temporary ground strap to the sender. If the issue is still evident, run a signal wire from the sending unit to the gauge. With a new gauge and sending unit, i would think that the issue is in the wiring. If the signal wire grounds intermittently, the gauge should read full, if the signal wire has an intermittent open short, then the gauge should read empty. I'm assuming you replaced the gauge with the factory spec. unit as well as the sending unit.

yes i ordered both the fuel gauge and sending unit for my jeep to factory specifications from morris4x4

i will try this out thanks

 

[mattduran]

So typical. Owned over 10 jeeps in my life and I think 2 have worked when I got them. Like Steelheadz said Process of elimination. Sounds like your getting power, are you hooked to (12volt switched) and all grounds are correct? Got to be one of the two. Good luck.

 

[jimbob2001]

Just. Like Steelheadz said: It is simply a process of Elimination! Three primary compnents in the FUEL GAUGE: 1. Gauge Itself. 2 The Sending Unit 3. The WIRING to Interconnect it all. You HAVE Replaced the Fuel Gauge and the Sending Unit -- Correct? Then in that case --- It is PROBABLY the Wiring--- Like Steelheadz said! Let's. Talk About Each Component -- Briefly. The Fuel gauge is actually. an AMMETER. The Sending Unit is actually a Pot. (Variable Resistor). The Gauge Varies between: FULL and EMPTY because the -- RESISTANCE varies between : 10 Ohms (full) and 73 Ohms (empty). That is it in a nutshell guys. Best way to TROUBLESHOOT? First, It is always a GOOD idea to get your Hands on a low cost DMM (multimeter) You can buy this at: Wal Mart, Radio Shack, or any Electronics Store. This will AIDE in the Troubleshooting thing! First thing to do: Remove pink wire from top of Sending Unit (sender wire to gauge)- Momentarily. SHORT this Pink wire (I think) to GROUND. Does GAUGE read FULL? IF it reads: FULL. Then thé GAUGE IS GOOD! If it. Does NOT Read FULL or does not Move at all --- YOU have a WIRING Problem. (DMM handy here). To CHECK your Sending unit (you will NEED DMM on the. OHMS scale) Remove Pink wire from sending Unit(wire from sender to gauge). One Probe on-- Post of sending unit (where pink wire was) One probe on GROUND. Should read like this (with sender installed in tank) 1. Tank empty-- 73 Ohms. 2. Tank. Half full -- 23 Ohms 3. Tank Full -- 10 Ohms. ANY reading Between -- 10 Ohms and 73 Ohms is OK!! Also: On your Gauge Itself--- 1. Is their Continiuty. (Short) between Pink wire (sending unit) and The S. Terminal on your Fuel gauge?? Also on your Fuel Gauge : Does your A terminal go to 12V? (HOT all the time). Also on gauge: Does your I terminal go to 12V - with. Ignition On? These three terminals: S. -- A.-- I. Are all ON the back of the Gauge. Hope this HELPS. Good Luck --- Keep us Posted! ------ JB.