My fuel gauge is pegged, but every now and then it will go back down, but seems to be messed up. I don't want to buy another gauge to clutter up the interior, any ideas??

 

bad ground, bad sender

 

Or an excessively GOOD ground. IIRC, grounding the sender lead will peg the gauge. Check the wiring to the tank and near it.

 

Man I have the same problem. Just swaped out Tpi for Carb now what? I have know idea where my fuel levels at. Some guy said a sensor. Well is the sensor controled by the ECM? If not where is the sensor located? I hope its not by the back of the tank. The guys at the shop ripped the old elec. fuel pump out for mech. I really would like to know something.

 

It just started to act up, several weeks ago, it would jump all over the place, and seemed fine, now it's doing it again, but seeming to be pegged and then working.

 

The fuel level sender is in the fuel tank.
It comes out with the fuel pump thru the top of fuel tank.
Unfortunately, it's not easy to get at.
The fuel pump can be removed and the remaining stuff (sender unit and metal fuel lines) re-installed.
You can drop the tank (and exhaust and rear-end), or you can do a hack job and get to it going thru the sheetmetal.
There's an elec connector on the drivers side (way up high) and just fwd of the fuel tank where you could disconnect and tell if gauge is getting a ground from somewhere between the connector and the gauge. Might save ya pulling the tank.

If all else fails, you can just use the trip odometer and tell when it's time for a fill-up.
Find out how big your fuel tank is, see how much it takes to fill it and you'll be able to get pretty close using the odometer.
My truck for example; when it hits 320 miles, I know it's time for a fuel stop. Truck has a 30 gal tank. (454's gas mileage sucks!!)
Seems like my Camaro was good for at least 200 miles between fuel stops.

 

My fuel pump is in the engine bay.

 

Having similar problem with 86 Camaro Z28. Gauge registers fine when fill tank, shut off ignition, etc. But can be driving along and needle will start jumping around. If had 1/2 tank gas will jump up to 3/4 and down to 1/4 roughly. Does not do all the time but more frequently than not. Any info would be appreciated.

 

Whoa, now that's an old thread. Way to use the search feature man, good job!
My car does this a fair bit, ever since I removed and replaced the cluster. The fuel gauge "wire" (the plastic sheet with copper in it), gets pinched by something else, and it pegs full. If I tap the gauge, it's enough to fix it for a brief period of time. Eventually I pulled the cluster, wiggled it, and bolted it back in. Has worked ever since.
Kinda a cheeseball suggestion, but have you messed with your cluster recently?

 

I'm having the same problem with both my gas gauge and my oil press guage. Both are pointing stright up, Can this be a fuse? The temp gauge and amp gauge are fine.