Fuel Gauge Troubles

[dave2953]

I recently swapped my cluster and did the rewire following the directions on GMCPaul's website. Initially when I hooked it up I had the tan wire in location 4 and nothing happened. They gauge stayed on empty. In my infinite wisdom I swapped the tan wire for a brown wire. (I'm colorblind and though maybe the brown wire could be tan til my fiance got home and set me straight) After I hooked the brown wire up the guage pegged to the 5 o'clock position and won't move no matter what. How do I fix it?? BTW, I checked the sender wire from the tank for breaks and didn't find any.

[1970shortbed]

mine had trouble it would go to empty if i hooked the wire ( to the sending unit)and to full if i unhooked the wire

i know yours is ok but it was grounded out and that was causing the problem

[dave2953]

ttt

[dave2953]

bump

[WorkinLonghorn]

This won't be much help but assuming you actually have gas in the tank and that the sending unit was known to be good then what I did was test the tan wire (to the tank) end to end for conductivity. I've had one that LOOKED good but wasn't because it got kicked or pinched in the door sill or something. If that wire is good then if you ground it the gauge,if it's connected right will go to empty.If it does,then the connection at the sender was bad or the sender was bad. If it stays on full the you have to connect it correctly in the cluster. That's all I know.

[dave2953]

I finally got the gauge working again. The sending unit tested good, so I replaced the sending unit wire and this made the guage go to "E". I then tried grounding the gauge itself and this fixed the problem. The brown wire I tried to use in place of the tan one has a full 12V and I think that fried the ground for the gauge, but I'm not certain. I ran the ground wire to the 3rd (lower) post on the gas gauge and this fixed it.

[LOW DOUGH]

I am going to have to check mine out. It always stays way over full. Every once in a blue moon the gauge works, maybe for 5 minutes or a day or two. So I bet the wire is bad. I always carried two gallons of gas with me so I new how far I could go to the next gas station. (Not Far)

[dave2953]

Is it at the 3 or 4 o'clock position? I think that is due to the sending unit wire being bad. Have you checked the sending unit itself with a multimeter?

[LOW DOUGH]

Originally Posted by dave2953

Is it at the 3 or 4 o'clock position? I think that is due to the sending unit wire being bad. Have you checked the sending unit itself with a multimeter?

I would say it is around 4 o'clock position. i haven't looked at it in awhile. Truck is not ready to drive so i don't pay atention to it and it is about 45 min. away. Out of the 7 or so years I have owned it' it worked maybe 3 or 4 times out of the blue.

[retodd7711]

How did you run the alternator wire? I am afraid to just start plugging in wires for fear of frying gauge. The FAQ says I need to make this wire, but how do I plug it into the gauge if I don't have the quick release pin connector?

[dave2953]

I didn't attempt that yet. I wasn't certain what to do either. I thought about trying to call GMC Paul's and seeing if they could provide some help. Their "tips" page says to call if you need more info. I might just take them up on that. Sorry I couldn't be more help.

[LOW DOUGH]

Oh, now i have the 69 tank and sending unit in the truck. I don't know what that one will do.

[BB72CHEVKT]

Anyone have pics of where the wire connects to the sending unit. I replaced the tank and am not sure where to reconnect. My guage stay at 3to5oclock.

[dave2953]

Here you go. I also took one of where it plugs in just in case.

[BB72CHEVKT]

Originally Posted by dave2953

Here you go. I also took one of where it plugs in just in case.

thanks a lot!!