Ok i have a 73 f250 and my fuel Gage wont work HELP. I have a after market and it works when hooked up but when i run through the stock harness i get not a on the stock gage. Do the voltage regulators go bad and if so how do i test went to dealer they said it cant be tested i don't think there right

 

I can't understand what you're saying. You're saying it "works when hooked up," what does that mean? Don't unhook it then, I guess? Please clarify what the exact problem is and under what conditions it manifests. Are you trying to run an aftermarket and stock gauge in parallel? What are you actually working with? Please explain this to me in a way that I don't have to ask questions.

 

I have a Sun flue gage in the truck right now which has its own wiring and i don't want to use it don't read right. I'm trying to hook up stock gage through the stock wire harness and the gas gage wont work. I have the wire right green with red strip but gage don't work. I know about the IPVR could that be bad and is there a way for me to test it to see if I'm getting the right voltage i know it should be 5.5.

 

Thank you for clarifying. You're right that there is a regulator that puts out about 5 volts, but not in a way you can measure with a meter (it's not DC). Hook up a test light to the sending unit lead, and you should see it blink about once per second. You're seeing the regulator PWM output "through" the gauge winding.

 

I don't get what your saying, test it at the tank where it plugs in ??

 

Yep, you got it. That wire runs all the way up to one side of the gauge; the regulator is on the other side of the gauge, and the gauge is close enough to a short circuit for these purposes. Check for blinking action at the signal wire that connects to the tank (make sure you have a good, clean ground for the test light - rusted over or dirty frame rail won't do).

 

So if its blinking and the gage don't work that means I need new volt regulator?? All my other gages (temp,oil and so on) are after market as well so I don't know if any of the stock works.

 

No, blinking = GOOD.

 

ok so blinking means volt regulator is good so that means I would need a new gage right

 

Not necessarily. Report your results and we'll go from there. Rarely do the regulator or gauge go bad; most of the time it's a sunk float, or bad ground at the crossmember. You asked about the regulator, so that's what I've described first.

 

I"ve been watching FMC400 electrical help, and he is usually right on the money, and he explains himself very well. If you do what he asks you to do you will fix your truck without buying un-needed parts.

 

After cleaning the ground REAL well, then when does the part about ......... the ....... to peg out the gauge happen?

That is a step in there somewhere, right? Ok I will set on the side lines and read and learn.

Sorry I usually fast fwd past the commercials....

fmc400 is to electrical issues like numberdummy is to part #'s and locations.