I have an 85 Camaro, 305 4 bbl. The Fuel gauge when 1/4 or more full reads way over at the 3 o'clock position and stays there until I get down to about 1/4 tank of gas then it starts bouncing between the half mark and the full mark, until I get about 1/8 of a tank left (the red marks on the gauge) then it reads pretty accurate. Any idea’s on where to start trouble shooting this, I am new to this car. Just picked it up about a month ago, so I'm not sure where all my sensor i.e. in the case the fuel sending unit is located, or any relays it may go thru.

 

Usually this is a bad sensor back in the tank. This is a wire wound resistor with a float arm to vary the position. The wires are real fine and when the wire gets broke it will read screwy until the contactor gets to a certain spot. Not a hard repair once the tank is out. Getting the tank out is the job.

 

this is what i was afraid of... Hopeing for a few other "check this first" but looks like tank may be comeing down this spring...

 

mine was bouncing like that too. When i installed my new gauge cluster it stopped bouncing.

 

it bounces because there is play in the gage needle. it suppsed to be difficult to move but its ok to wear away, mine bounced everywhere too till i replaced it. but the real reason itll go all the way to 3 O'clock is because when you start the car the gages all go funny looking, the gas gage goes to full and oil goes to full press. the gas gage needle stops going up because it hits the gage bezel, but if the bezel is bent then itll keep goin and get stuck.