Jetdriver69

Is the fuel gauge wired through the fuse panel? My gauge quit working but haven't got around to pulling the sender from the tank yet. The low fuel warning light works but gauge is showing completely empty. Two of three leads on top of the sender show good continuity, but the second power lead shows open circuit. I am thinking a broken wire on the sender, any suggestions?

jpitman2

Model year please - it is relevant in this case.
The low warning means that at least power is getting to the sensor, and one signal is coming back, so its a little unlikely that level wire has failed, but still possible. Does the low fuel warning go out when there is more than the reserve in there? The low fuel is triggered by the float making a contact at the bottom of the tube, so if it goes out, it means the float is rising somewhat. Check Sharkskin's excellent pages for details of how the sensor works, and how to dismantle and clean it. My gauge didnt work because the small wiper parts that slide along the wires had got bounced out of place - there is a wiper on each side of the float shped like a > and each should have their point facing the wire like >| so there is a little pressure on the contact. One of mine was ok, but the other was like |> so they could drift away from the wire and break the circuit. If the circuit is broken like this , it doesnt matter what the float does. You should also CAREFULLY clean the wipers and the wires to remove any dried fuel stuff off them, and check the resistance - should be ~ 80 ohms at one end, close zero at the other end.

look here...http://members.rennlist.com/sharkski...ugeGremlin.htm
You can see the V or > shaped wipers in one pic.

jp 83 Euro S AT 55k

Jetdriver69

Sorry, its a 82 5 speed. The gauge failed once before and I cleaned the contacts on the sender and it worked again. My low fuel warning does come on when starting the car as part of the warning lights test but then goes out as normal. I filled the tank up about 150 miles ago to move the float with no effect. The gauge failed after I removed and cleaned up the fuse panel and repaired some frayed wires and the needle is stuck at full empty with no low fuel light illuminated. Is the connector in the spare tire wheel well behind the plastic plate used for the fuel sender and is there a connection in the fuse panel?

Thanks

jpitman2

Yes, the 3 pin connector in the spare wheel well is relevant - clean it well on both sides, and check. See the detail on the Sharkskin pages....you should see ~5V at the power into the gauge head in the tank (ign on). If you do, try shorting the +5V to one of the other two connections (connector removed from tank unit) - one should give you low fuel light, the other should give tank full reading - ~40 Ohms should give around half. There are connections on the fuse panel - I will look up tomorrow and come back if nobody else chimes in with the connection points.
jp 83 Euro S AT 55k

jpitman2

Here is what my wsm shows:-
G at the gauge head tank unit (Violet/black) ->T3 ->H3 ->5L (instrument panel, contact 5, left connector) - fuel level.

W at the tank (Yel/black) ->T4 -> H4 ->central warning unit 16GE. This will be low fuel warning

Instrument panel Contact 4, left connector is fed by CWU pin 3GE.

So at the central board, T3,T4, H3, H4 are the points to check.

jp 83 Euro S AT 55k

tom-in-tempe

The fuel gauge in my 86 was not working, stuck on empty. Had checked the float, all looked fine there. Was replacing the odometer gear and while I had the gauges out figured I'd give the fuel gauge needle a flick. I did seem to be a bit stuck at the bottom. Put the dash back together and now it works fine. The needle was just stuck at E. Not saying that's your problem but it worked for me.