Tried to jump start my 50 Chevy and accidentally crossed the jumper cables!! Of course now my fuel gauge is REALLY dead. It has a Runtz on it-maybe I killed it and not the gauge?? Any thoughts?!
Ok I did, and I killed the reducer alright. But I had a spare one, installed it, and the gauge reads once again. But as before, after ***uring the integrity of all ***ociated wiring, it only reads at the first dot on the gauge. I have roughly a half tank of gas in it. Now. When I disconnect the wire to the sending unit, it pegs full on the fuel gauge. Does this mean the gauge is working but the sending unit is junk? Thanks for any help!
It may also help to know that when I test the wire going to the tank, it reads 2 ohms. Of course it is disconnected from the gauge when I do this.
Here is how you normally test a fuel gauge and sender: Remove the wire from the center of the sender (the one that goes to the "S" terminal on the gauge) and turn the key on. Then touch that wire to the grounded part of the sender and the gauge should peg "full". If it does that the gauge and the sender wire is ok. Then you have to remove the sender and hook the wires back up (making sure you have a good ground to the sender body) and move the arm up and down. With the key on the gauge should go from empty to full as you move the arm up and down. (Be careful not to make any sparks around the fuel though) There are 3 basic components in that system, the gauge, the sender, and the ***ociated wiring. What you are doing is process of elimination to find which component (s) are not working correctly. Don
Well, maybe for your setup. "Normally", the sender provides varying resistance to the gauge and when the gauge is supposed to read "full" the sender is at minimum resistance, just as if you were grounding out that wire. It could be that yours is designed to work just the opposite. But the fact that you are able to get the gauge to deflect through it's range by doing that kind of tells me the gauge is ok and the sender is screwed up. Hard to diagnose via keyboard though, it is one of those things you have to actually have in front of you to figure out. So, has this gauge never read right ? Here is a pretty good write up on the subject: http://auto.howstuffworks.com/fuel-gauge.htm Don
I already checked the wire to the sender, by disconnecting it for the gauge and the sender. I checked it for continuity, and to see if it was grounded some where. Nope, wire good
I wonder if I might be on the wrong terminals? And the gauge just never registered at all to begin with Don the man!
Very kool!!! Alright, I dropped the tank (pretty easy) and yanked the sending unit. Wired up the one wire from the gauge to the sending unit, and then grounded the five bolt flange area of it. Raised and lowered the float, and the gauge joyfully responded proportionately! Yaaay! Looked at the br*** float and it had a dent/crack in it (full of gas)-how the hell do you dent that??? Must have been lying in the bottom of the tank. I'll just get a new sending unit now. Anyway-thanks for the help guys!
Haha, I am happy for you ! It is tough to drive a car with no idea how much fuel you have in the tank. Don
I thought on some GM cars that IS normal.. Fords are always on Empty with no connection, full when shorted.
I don't see how crossing jumper cables can disturb anything beyond the battery. A short is a short that only travels though the short. Kind of reminds me of Ghostbusters -- "Don't cross the streams!"
Just finished up installing the sending unit-all working good now! Note to self, next time do it with an empty tank. But fortunately I keep my feathers number for such an occasion!
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