I've seen various references to this problem in other BBS, but no good diagnosis.

Here's the story. We have a 2003 Z71 with 80K miles (this baby has to get us to 200k). When the fuel gauge gets below 1/4 tank AND it sits over night the car will not start in the morning. Add 3 or so gallons of fuel and it will start.

The car will continue to drive and run past 1/4 tank if on a trip, it will also restart if warmed up when the gauge is below 1/4 tank. Therefore I don't think its a gauge related issue.

To my inexpert thinking it appears to be related to the fuel sending unit needing a minimum level (or weight) of fuel to pump correctly when its cold?

Thank you for sharing your expertise.

 

Welcome.
This problem is often caused by contamination in the fuel and can normally be remedied by replacing the in-tank fuel strainer with an updated part GM part # 19122083 and also the fuel level sensor kit with GM part # 88966959
There is no need to replace the fuel pump module.

Make sure that the fuel tank is drained and flushed during the repair or the problem may reoccur.


Dave