Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Running out of gas at 1/2 tank?

Hello All,

I have a 1999 GMC Yukon SLE. I’ve recently noticed that I appear to be running out of gas at the 1/2 tank mark. When I go to fill it, it seems I really do still have 1/2 a tank of gas (so it doesn’t seem to be just a bad gauge). As long as I keep the tank above 1/2, everything is swell. Anyone got any clues what might be causing this?

Thanks for your help!!

When you think you’re running out of gas, open the gas cap and put it back on, then see if that makes a difference.

Can we clarify what you mean when you say the vehicle “appears to be running out of gas”?

A. The fuel gauge incorrectly reads EMPTY when the tank is really half-full, or
B. The engine sputters and stops running, or becomes difficult to start, which is what happens when a car really runs out of gas.

Thanks and the experts on the board might chime in once we understand the exact symptoms you’re seeing.

Clarification: What I meant to say is that “the engine sputters and stops running, or becomes difficult to start…” at the 1/2 tank mark. Hope that helps. Thanks for the responses.

You’re gonna have to have a look inside the tank to determine if your pick up tube is all there yet, the sock filter is all plugged, or your fuel pump is shot. Next step, drop tank and take a look see.

Thanks for the info.

Footnote, You should get a fuel pressure tester on it both when its ok and when its having problems first to see if you got low fuel pressure anyway.

thanks Bing…will do

It’s a plastic fuel pump. I bet there’s a crack somewhere on the fuel pump assembly that when it reasches a half tank it loses fuel pressure.


thanks tester