Fuel Gauge stays FULL then drops to HALF
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From: Stoughton, MA
Car: 1985 camaro Z28
Engine: 305 5.0 V8 carburated
Transmission: 700r4
Fuel Gauge stays FULL then drops to HALF
Every time I fill my tank, the gauge says it's full. Seems alright untill a day or two later it hasn't moved at all, as if it is stuck.
Eventually it drops to read about half a tank. Is the needle getting stuck at full and just gets unstuck when i hit a bump or something? I just want to make sure it's reading right. If it's showing a true half tank when it goes down to half, then that's perfect! How do I check to see if it's reading right?
I searched but all of the other threads talk about it just being stuck on full. I wasn't sure if it was the same problem.
Eventually it drops to read about half a tank. Is the needle getting stuck at full and just gets unstuck when i hit a bump or something? I just want to make sure it's reading right. If it's showing a true half tank when it goes down to half, then that's perfect! How do I check to see if it's reading right?
I searched but all of the other threads talk about it just being stuck on full. I wasn't sure if it was the same problem.
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Joined: Sep 2002
Posts: 9,192
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From: Cary, North Carolina
Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
Re: Fuel Gauge stays FULL then drops to HALF
The guage sender has a float that rides up/dpwn on a rod - probably rust/funk buildup on the rod which keeps the float from riding it smoothly.
Calculate your mileage and set trip meter every fill up so you know how many miles you have left.
Calculate your mileage and set trip meter every fill up so you know how many miles you have left.
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Joined: Feb 2011
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From: Phoenix AZ
Car: 1991 Camaro Convertible
Engine: Hellifi-no special
Re: Fuel Gauge stays FULL then drops to HALF
Yeah, mine does something simliar. Stays at over full, until the tanks is almost empty, then the gauge drops to 3/4. I'm thinking sending unit, also. God knows what the inside of that fuel tank looks like. If I get to it before you do, I'll let you know.
Thread Starter
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Joined: Mar 2009
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From: Stoughton, MA
Car: 1985 camaro Z28
Engine: 305 5.0 V8 carburated
Transmission: 700r4
Re: Fuel Gauge stays FULL then drops to HALF
When I bought the car, it appeared that somebody replaced the pump or something because they did the "hatch" method and you could see the tubing attached with some hose and hose clamps. If I EVER get the chance to look at it, I will.
Thread Starter
Senior Member
iTrader: (1)
Joined: Mar 2009
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From: Stoughton, MA
Car: 1985 camaro Z28
Engine: 305 5.0 V8 carburated
Transmission: 700r4
Re: Fuel Gauge stays FULL then drops to HALF
Yesterday I noticed that the gauge would seem to work correctly. It was reading full because I filled it the day before, and I was a long drive which dropped it to 3/4 of a tank. This made me think it was reading correctly. This morning, on the way to work, it dropped to half a tank. I don't get it.
Re: Fuel Gauge stays FULL then drops to HALF
It could be the sending unit or bad contacts on it. Depending on the age of the car, it may be the unit itself. I am going to be making a hatch and replace mine, I will also do the fuel pump at the same time. My car is an 87.
Thread Starter
Senior Member
iTrader: (1)
Joined: Mar 2009
Posts: 817
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From: Stoughton, MA
Car: 1985 camaro Z28
Engine: 305 5.0 V8 carburated
Transmission: 700r4
Re: Fuel Gauge stays FULL then drops to HALF
Well, I took it apart again and Moved the contacts a little bit and bent the other contact to stay tighter to it, and it seems to work better now.
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