Is it Common for This to Happen?
 

When my fuel gauge gets between half and a quarter tank the needle moves up and down with turns and acceleration. For instance I was getting off the highway on a long swooping ramp and the gauge plummeted to E, but when I was stopped at a light afterwards it went back to almost halfway. I did a search and found out about the wedge shaped tank and how half a tank is closer to one quarter etc. but should the fuel move that much? Is there no baffling in the tank? Or do I need a new gauge sending unit/sensor? Above half a tank it doesnt move at all.

I have this same thing happen in my 3.8

when you get that low on fuel it doesnt take much to make the sensor float jump around.

Thanks guys. I guess it makes sense that since the gauge is off it would be more sensitive as the fuel level goes down.

ya for instance my Z runs out of gas at an 1/8th tank

GM biggest prank but nobody is loling. It is normal I went from 3/4 to 1/4 today with a Sharp turn.

its when it stops jumping around that your in trouble.

gm fuel gauges have always been guesstamations even back in the 60s,my 86s fuel gauge will only show sorta right if i park it for a minute.your best bet is keep it near full and try not to put much faith in it

I always go by the trip meter. I faithfully reset mine. And then again, it goes by your driving style. At 200 miles, I'm looking for petro. At 250 miles I'm sweating. My driving style is mostly cruising, and making sure the exhaust, engine light up about once a day. Mine has 8 holes in the block BTW. I average 20-22 MPG. I know, pretty lame driving.

Thanks everyone for the comments. I fell better now, I will just keep and eye on the gauge. It actually went pretty close to E before I started this thread and when I filled up it only took 14 gallons. I think I can fill up around 1/8 tank to play it safe.

I drive mostly highway, but since this is a new to me car (mine is a Z28 also) I have run through the gears a few times with my foot planted. So far the needle it at 3/4 of a tank and I have driven 200 miles. I expect to get 300-350 out of this tank.