my gas guage has been on empty ever since i purchased my 71 dart. I was told the sending unit. Doesnt' the sending unit have other responsibilities? wouldn't these other responsibilities quit as well?

I'm not sure how to test the unit. 12 volt light? how and where?

thanks! drew

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71 Dodge Dart Custom 4-Door. 86K original. A/T. Blue with white vinyl top. Blue interior. 225 SL6. 1 barrel, new fuel pump, autolite platinum plugs, fuel line upgrade, new shocks, new drum brakes and hardware, A/C, all stock

The sending unit's only function is to vary its resistance according to the level of fuel in the tank, thus "sending" that information to the fuel gauge on the dashboard. If your gauge always reads empty, the sender could be faulty, or you could just need a new sender float, or there's a break in the wiring, or there could be a problem with the gauge itself in the dashboard. Does the engine temperature gauge work? If both of these gauges are not working, the likely cause is the instrument cluster voltage limiter, which is plugged into the back of the dash. You can check the sender by removing the wire from it and using an ohmmeter to measure the resistance between its terminal and ground. If it is infinite (open circuit) then you've got a problem with the sender itself. If it is high but finite, even though you've got lots of fuel, then there's probably a float issue. If it's within the appropriate range as specified in the service manual, then plug the wire back on, disconnect its other end from the back of the instrument panel, and see if you can duplicate the resistance you found, measuring between the dashboard end of the wire and ground. If not, it's a wire problem. If so, it's a gauge problem.

You'll definitely want to buy the factory service manual and probably the other two books described at this link. The Chilton, Haynes, and other aftermarket books just aren't good enough.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

The problem could be as simple as a bad ground. You can check the ground by testing the continuity between frame/body and the tank.

If you find the tank & body of the car are not electrically connected just run a #14 wire from the outer edge of the tank seem and frame secured with sheet metal screws.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Not to hijack the thread here, but my 71 Dart has the same problem. It has the fuel gauge reading empty, and the temp gauge also does no work. Can this be fixed?

I dont have the money yet to get the factory manuals, but Politpaul has told me he has them when I have the money.

I just want a temp and fuel gauge, I am about ready to just put in aftermarket stuff, but I would like to have function of the factory gauges as well.

~The Other Rob~

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1984 D100 Shorty Custom
Certified Auto Appraiser - RevItUp Classic Appraisals
President - Cherry City Bombers CC
Part of Tyrde-Browne Racing

Yes, usually. Like Dan said, it's often the instrument voltage regulator/limiter, or sometimes a ground issue.
New REGULATORS are availble, including solid-state LIMITERS.
Some of us just adapted 7805 regulators, as done HERE.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

Your Voltage limiter may be not working if both the temp & gas gages don't work. Or, you have some cooked wires, or circuit board that supplies the gage cluster due to an 'over current' condition.

You will have to dig into the dash and inspect the gages and board for damage, as well as tracing out all wire or conductors associated with the two gages looking for corroded connectors, and bad wire.

Be sure to disconnect the battery before working on the electrical system.

Below are two solutions regarding the voltage limiter.

http://www.yearone.com/pco/A_0308/full.asp?page=91

http://www.demonivr.com/index.html


This is what I did to repair the gage circuit board for my 67 Dart: soldered a few leads to bypass the pin connectors feeding the board. Also I replaced all the brass connectors & some burnt wire feeding the gas gage & temp gages.

http://i294.photobucket.com/albums/mm87 ... 0_0643.jpg

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

http://www.earlycuda.org/tech/gauge-convert.htm

http://1962to1965mopar.ornocar.org/ml-i ... tor64.html

http://www.allpar.com/history/mopar/electrical2.html