2nd Gen Non-Engine/Transmission Eratic Fuel Guage

[BIG BOB]

For the last 6 months my fuel guage has been acting up. At times when I am driving the fuel gauge will start dropping, and finally the low fuel bell rings and the gauge continues to empty. I'll shut the truck off to cycle it while I'm driving, it may take a couple of times cycling from off to on, and then the fuel gauge will go back up to where is suppose to be. It seem to happen more in the hot weather.



I have done a search and read many post of people who have had problems with their fuel gauge, however, none have seemed to have this same problem.



How about it, anyone have this problem?

 

[blacksheepdiesel]

I have had the same problem on my '89 for over a year. In my case I believe the sending unit is bad because the gauge will drop suddenly from about 1/4 tank to empty yet the low fuel light won't come on. After several miles the needle will come back up. I also have noted that when the gauge is showing low on fuel AND the fuel light is on that I can only get about 24 gallons in the tank and it holds 35. That's what tells me the sending unit is going wacky. I choose to deal with it by waiting until the light comes on before filling up. Glad I don't own a gas burner 'cause I wouldn't get very far before filling up. Thanks Cummins!



Trent

 

[rjahde]

Check the sending unit wire connector at the fuel tank.



I had the same problem with erratic gauge and that is what it turned out to be.

 

[Loren]

Big Bob,



Mine acted a lot like yours. I never tried cycling the "ignition" switch on and off. Never thought of it.



I hope it's just the connector, but on my 1995 truck it turned out to be the sending unit in the tank. You have to disconnect the fuel supply and return lines, the fuel quantity electrical connector, and the filler hose, and drop the tank.



The in-tank unit, including the fuel quantity sending unit, unscrews from the top.



It seems to me that some mechanics were able to rebuild these, so you may be able to try that. As I recall, there is a pivot that can be rebuilt to provide a better connection on the sliding resistor (?). If you inspect it, I'm sure you can see what needs to be done. Mine was too far gone, and I had to replace it.



Good luck.

Loren

 

[BigDon]

I, too, have experienced the erratic fuel guage problem for a year or so. I am assuming that it is a connection problem at the fuel tank. The instrument panel guage test works fine and the fact that the low fuel light and chime come on tell me that there is a connection problem. As this happens every couple of months or so, and is short-lived, I have not had the desire to drop the tank to check it out. Eventually it will get bad enough (as all things do) and I'll have to go that route.

 

[IWeiny]

Do you use a fuel additive?

I went through 6 or 8 sending units between the 98. 5 I returned as a leamon and my 99 combined.



After I lost the lift pump I quit using the additive and the problems never came back. I thought the issue was the additive.



After joining TDR and reading this site I am not so sure?