2003 Tahoe will not crank with a half tank of gas

[shadetree99]

I have a 2003 Tahoe z71 4X4 and with a little under a half a tank of gas it will not start. If you add a gal. or so of gas you can hear the fuel pump pick it up and then it will start. What could be causing this?

[jdl]

I looked up some service bulletins on your fuel system. There were several about improper fuel gage readings. The gage shows more gas in the tank than you really have. I don't know if that is your problem?

You might call your local chevy dealership, talk to the service department. Some service departments will talk to you and try to help, some won't. It don't hurt to ask.

I realize this probably isn't the answer you wanted.

Maybe I misunderstood your post, you are saying the starter won't even crank? Or does it crank good but won't start?

[shadetree99]

The Tahoe had appox. 8 to 10 gallons in the tank and the fuel pump would not pick it up. I added about 1 to 2 gallons and you could hear the fuel pump load up after the gas was added. When the fuel pump picked the gas up it would crank ok. It acted like it had lost prime and would not pick up the gas in the tank. It has a 26 gallon tank and when i went to the gas station to fill it up to make sure it was not the gauge it held 16.5 gallons.

[jdl]

Unless the tank was low, I can't see how adding a few gallons, would make any difference. I think the pump should run even if the tank was empty. I don't know how easy it would be to hear, my hearing is no good. I don't know how much gas it would take to cover your pump, maybe the pump is overheating?

When you turn the key on, no crank, can you hear the pump run for a few seconds. If you can, is there fuel pressure?

Did you check for any codes? Some national brand auto-stores will check codes for free. I don't usually get that lucky, usually there aren't any codes.

[jdl]

Originally Posted by shadetree99

The Tahoe had appox. 8 to 10 gallons in the tank and the fuel pump would not pick it up. I added about 1 to 2 gallons and you could hear the fuel pump load up after the gas was added. When the fuel pump picked the gas up it would crank ok. It acted like it had lost prime and would not pick up the gas in the tank. It has a 26 gallon tank and when i went to the gas station to fill it up to make sure it was not the gauge it held 16.5 gallons.

I need to make sure we are on the same page, when you say the vehicle won't crank, that means the starter won't work. Is that what your saying?

The starter won't work unless you add two gallons of gas?

Just to add, if this is a starter issue rather than a fuel issue, when the problem occurs, and you try to start it, is the theft lite flashing?

[rickp0001]

I hav an 02 Tahoe LT and I have the same problem. My truck will not start with just over 1/4 of a tank of gas as per the gauge. I add 4 gallons and it starts right up.