Fuel gauge problem?

Well, im use to it by now, but i think it's a problem that i need to know about. When my car is reall low on gasoline, lets say about 5 gallons or so, and it the fuel gauge needle flips and flops around, from left to right. And when i put a half a tank to a full tank of gas it doesnt wiggle around. So, what i need to know is, what's wrong here?o No: My grandpa said it was that way ever since we got it. I talked to a junkyard in fort madison(one of iowa's little towns) and they said it might need a new float in the tank. I also talked to some mechanic in hamilton Illinois and he said some of the older cars have the same thing happen, and it's no biggie. I think there is a problem. Am i righto No: Any help is greatly appreciated. Thanks

-Cody

 

i would check the resistance of the the sender unit... clean the Earth contacts and maybe fix in some new wire, if the old stuff looks shot.....my 55 had/has a fuel gauge prob that, it would never read empty... theres a few times i ran out of gas...lol. before i realised i had a prob...the gauge worked sweet from full to 1/4 tank...but i eventually discovered that even if i drained the tank it would never register below 1/4 tank...
replaced the wires, clean the earths,checked the sender and it works a hell of alot better...still a lil temperamental from time to time.. but it is better... go for the simple stuff first before ya look into replacing it.
most of the time stuff like this is just old wire that has got tired n needs replacing.

 

What you are describing is quite likely normal. Most of the older GM cars all did that. My Riv does it a little, but the 3 skylarks I owned in the past all did. It's from the fuel sloshing around in the tank.

Just be glad you don't own my son's '86 Merc, his guage still shows 1/4 tank when there is only a gallon or two left in the tank. (artermarket sending unit) So far he's run out of gas twice.:af:

 

Thanks. I will check into some of those things when the weather gets a little better.

Nailheadina, your son's 86 merc sounds like the aftermarket sending unit is a real winner

Thanks for the help

-Cody

 

Can be just like a radio knob. The place where the wiper on the potentiometer moves across the most will get get worn and a deposit will ensue. Thus you get an intermittant reading. This manifests itself on the volume side control of the radio as a scatching sound or a dead spot. If all terminal points are good, drain the tank, drop the tank and replace the float assembly. The one for a GS is about $75.00 from www.GMpartsdirect.com.