Ok so I just bout an 05 silverado 1500 with the 5.3, while I was driving the truck home I think I had hit a little bump and the truck just died on the side of the road, it took a little time good the truck to start back up again which I'm thinking it was bad fuel because the truck had been sitting for awhile.Well it ended up happening 1 more time in the 2 hour trip it took me to get home. The check engine light was on for the knock sensors and the rear o2 sensors. So I sent the computer off to aggressive motorsports in Edinburgh tx so they could tune out the o2 sensors and a few other things. Well i just got finished changing the knock sensors out and putting the computer back in so I go out and test drive it, the truck ran awesome for like the first 5 minutes and the truck all of a sudden dies again but it starts right back up like nothing ever happened?? I went out and bought a fuel pressure gauge, connected it to the rails and it stays steady at around 60 psi, even when the truck dies the gauge still is shows around 60 psi. I'm at a stand still here I dont think its the fuel pump any more since.the gauge stays steady around 60 psi am I right? Ive read to check the fuel pump relay bu of course this truck does have the fuse box lid so I have no diagram to look at and see which relay is which. Has anyone ever heard of a problem like this?

 

When you try to start the truck you're getting no fire not even trying? Have you tried cycling the key a few times to prime the pump? Do you hear the fuel pump hum?

 

No the truck will start right back up after it dies like nothing ever happened

 

can you take a video of it?

 

How can I upload a video with my phone?

 

either with YouTube or photobucket

 

I've seen vehicles do this when they lose a crank signal. Lots of times a code will never be reported as it's not a wire/voltage failure, but just that it lost the signal for that quick instance and that in turn told the PCM that the motor wasnt running anymore and shut everything down.

Kinda common on 3800.

Not sure how much that helps, but something to keep in mind maybe.

 

Sounds like it may be an electrical gremlin somewhere. If the gauge is reading 60psi the entire time even when it cuts out, we can assume that the fuel system is okay.

I would start looking at the grounds. Especially since you said it happens after a bump. If a ground is loose or not making a good connection, jarring it can make it lose connection for a second and you could be losing spark, cam/crank, etc. There are several going to the frame, also look at the ones on the cylinder heads as several circuits ground there as well.

Also have a code reader ready and see if there is anything pending that might narrow it down for you.

 

I would bet it's the electronic switch on the Key cylinder.