Starts and instantly dies

[ArgyllshireAndy55]

I have a 2001 Silverado 5.3 with 145,000 miles.
It runs great, lots of power and starts immediately, except for the other day.
I drove to work and it was up to full operating temp, shut it off and came out 2 hours later and it cranked just fine and fired but died immediately. Repeated attemps got the same results. It would run for about 1 second and die. I tried starting it about 10 times in a row. I tried it again an hour later and its run perfect for the last 2 days, no hesitations.
The outside temp was about 65.
No check engine lite or any other lights came on.
No weird sounds.
New battery.
The fuel pump was changed out at a reputable Chevy dealership 3 years ago and about 40K.
I havent checked for any codes, or fuel pressure.
It acts like a fuel pump failing, hiccups once in awhile and then leaves you stranded when you least expect it.
But.....It started up instantly after sitting for an hour, meaning it had fuel waiting in the wings.
I am thinking its likely electrical, a sensor? But shouldnt I be getting a light?
Any ideas?
Thanks, Andy

[j cAT]

Originally Posted by ArgyllshireAndy55

I have a 2001 Silverado 5.3 with 145,000 miles.
It runs great, lots of power and starts immediately, except for the other day.
I drove to work and it was up to full operating temp, shut it off and came out 2 hours later and it cranked just fine and fired but died immediately. Repeated attemps got the same results. It would run for about 1 second and die. I tried starting it about 10 times in a row. I tried it again an hour later and its run perfect for the last 2 days, no hesitations.
The outside temp was about 65.
No check engine lite or any other lights came on.
No weird sounds.
New battery.
The fuel pump was changed out at a reputable Chevy dealership 3 years ago and about 40K.
I havent checked for any codes, or fuel pressure.
It acts like a fuel pump failing, hiccups once in awhile and then leaves you stranded when you least expect it.
But.....It started up instantly after sitting for an hour, meaning it had fuel waiting in the wings.
I am thinking its likely electrical, a sensor? But shouldnt I be getting a light?
Any ideas?
Thanks, Andy

with the issue you have, no failure codes the fuel pressure will need be checked when no engine run .

replacing the fuel pump requires the splicing in of connectors. they may have done a poor solder/crimping job and the wire joints are corroded.

when replacing the fuel pump at this age, the fuel relay should be replaced along with the fuel filter.

could be a fuel pump . keep the fuel level above 1/4 tank.

the other problem may be the vehicle security .

[ArgyllshireAndy55]

Thanks Jcat, I appreciate your input.

I havent had it happen again but sure it will.

I was thinking if the fuel pump was failing intermittently then it wouldnt have started up instantly after it sat for an hour, it would need to pump for a bit to pressure the rail.
I am thinking about your security system idea cutting off the ignition.
Thanks again,
Andy

[j cAT]

Originally Posted by ArgyllshireAndy55

Thanks Jcat, I appreciate your input.

I havent had it happen again but sure it will.

I was thinking if the fuel pump was failing intermittently then it wouldnt have started up instantly after it sat for an hour, it would need to pump for a bit to pressure the rail.
I am thinking about your security system idea cutting off the ignition.
Thanks again,
Andy

If your fuel pressure is on the edge 50 psi. this start issue can be intermittent. checking the pressure if its 55psi engine runing and 60 psi key on engine off then the fuel pump or circuits to it should be good. sometimes the ground at the frame rail next to tank or the pump relay are the problem. could also be loose fitting fuses etc.

the pump need a good ground and 12volts.