2002 Z71 Starting and Fuel Issue

[cmark]

Hello and thanks for whatever help you can give...

I have a 02 Z71...for about a year now I have had a major issue and no one is able to diagnose the issue. They keep hooking it up to the computers and everything checks fine.

The issue is whenever my truck gets to about a quarter tank of gas and its sits for overnight, lets say 12-15 hours it will not start, it just cranks and I know the problem is that its not getting fuel.

Here is what I know...1) I have no problems when driving and letting it go below a quarter tank just as along as I put fuel in it before I let it sit overnight. 2) I know there is at least 5 gallons in it when it doesnt start because I have put gas in it and it started and then went to fill and watched how much total fuel I put in. 3) when it doesnt start and I unscrew the gas cap there is no pressure release like you normally here when you put fule in the truck. 5) I do have a service engine light that is on perpetually but the service people just say its evap code for emissions.

I am not sure if its the pump or I have a hole somewhere in the fuel line and it bleeds pressure on low fuel. Any suggestions please...I am not a mechanic.

 

[justimagination]

:welcome:to the forum. The fuel pump do have a screen filter internally attached, some people used to call them a sock filter. Sedement will always go to the lowest point. So naturally when your fuel gets close to the bottom, the clogged portion will restrict fuel flow. My suggestion is to replace the fuel pump with nothing but AC DELCO, as well as the external in-line filter, also AC DELCO. If you have a AC DELCO parts distributor in your area, you can get a wholesale price saving quite a bit of money. JMHO and good luck.Keep us informed. :waytogo:

 

[peteyz71]

Has anyone removed the gas tank out and pulled the sending unit? I have a '94 Chev pickup as well as my '04 Tahoe. Thr '94 would act weird when it got low on fuel. Thought it was a failing fuel pump. Went to install new fuel pump, pulled the sending unit, and found a crack in the hose connected to the fuel pump. As long as the crack was submerged, everything ran well. Put in a new piece of hose, and its still on the oringinal pump at 195k. Perhaps you have something similar going on in the tank when it is lower on fuel?? Just a thought.