i have a 84 trans am and the fuel gauge stays at full all the time. what can be the problem. a friend told me i can use my two fingers and gently put pressure on the fuel gauge and it will give me an estimate of how much fuel i have in my tank. is that true? and what can be the cause of the problem and how can i fix it.

 

I think your friend may be trying to put one over on you.

There is a sending unit in the fuel tank that tells the gauge how much fuel to display. Its not an easy thing to change. My IROC fuel gauge doesn't work either, I just reset the odometer every time i get gas. Then when it gets to 200 miles or so, i fill it up and reset it. Its kind of a waste to not use the 18 gallon tank i have, but more gas in the tank keeps the pump cool (which prolongs the life of the pump).

If the pump ever does go out, you can change out the sending unit then.

 

If the wire from the sending unit to the guage has been cut or damaged it will read full. I recently ran into the same problem while screwing around with ****. Yours is probably in the same place if you want to trace it. Fold down your back seats. lift the carpet closest to the seat and right in the middle, under the carpet you should have a black connector that has three wires. One 12v, one ground and one ( pink wire ) going to your sending unit. Behind this plastic connector the three wires will go straight into your tank. The power and ground are for the fuel pump and the other of course is for the sending unit. I'm not quite sure if that sending unit has power tapping off of it from the fuel pump 12v or if the guage just holds the power and reads what the sending unit is sensing. I'm sure someone here can answer that but... I'd trace that pink wire and look for a pinch or cut. Fwi... oddly I think on the other side of the car, the pink wire becomes a different color... I'm going to double check mine soon, I'll let you know if thats true.