2000 Chevy Silverado 1500 4x4 5.3L Fuel Pump Problem?

[mp2008]

I own a nice 2000 chevy silverado 1500 4x4 5.3L.

 

The last couple months, when I've went to start it up, it has rolled over about ten times before starting up. Sometimes I even have to pull the key back then roll it over again to get it to start. However, if I start it within 5 minutes or so of turning the engine off from driving, it will start right up. Anything over ten minutes or so, it wI'll do the roll over problem.

 

I was talking to a family member who's a former mechanic and he said it sounds like a fuel delivery problem, possibly the fuel pump. He told me that every time I go to start it, turn the key forward, sit for a bit, turn it back, then turn it forward, let it sit again, and then start it. Every time I do this it starts right up. He said it's most likely something with the fuel pump where it's not building pressure and sending fuel fast enough. By doing his suggestion, it turns the fuel pump on and allows pressure to build in the line and get fuel to the motor before I try starting it.

 

The fact that it starts right regardless within 5-10 minutes after shutting it off supports this theory because there would still be fuel and pressure in the pump/line. After 10 minutes it losses pressure and does the roll over problem.

 

Just wondering if you guys agree with this assessment? Was going to buy an AC Delco fuel pump from rockauto.com but I want to be pretty confident that's the problem before I spend even more money on this truck. Fuel filter was replace just in case and that didn't help, thoughts?

[muddkatt]

Its the fuel pump. My 2001 is doing the same thing right now. My guess is its losing its prime and takes 2 times to fill the lines and build enough pressure to fire up.

I would buy the AC Delco pump and avoid the ones from Autozone etc.

[rjgti]

why not hang a gauge on the rail and see if it is pressure reg problem, much easier to change

[muddkatt]

How will testing the fuel pressure diagnose whether its the fuel pump or a pressure regulator?

[rjgti]

when pump shuts down pressure will not bleed off of the rail

[mp2008]

Do you know if there's a pressure check port on these trucks and where it's located?

[rjgti]

passenger side fuel rail has a port for it

[00Silverado4x4]

https://www.youtube.com/watch?v=53w5v7CHpCQ

 

This is on a 2001 but should be the same location.

[mp2008]

Alright, thanks guys!

[muddkatt]

when pump shuts down pressure will not bleed off of the rail

It will still bleed off if the check valve on the pump is bad. You check the regulator by pulling off the vacuum hose to see if fuel is present.

[intheburbs]

My '01 Suburban fuel pump died without ever showing any type of symptom like that. The fuel pump whined for a few months prior to dying, but right up until it did, it started up right away. Got in the truck to go out for dinner, it started up just fine as always, pulled out of my neighborhood, and the truck just died. Odometer was around 130k, IIRC.

 

Turn on the ignition, but don't start the engine. Listen for a whine coming from the tank. If you don't hear the whine, it's probably not a fuel pump problem.

[mp2008]

From doing a bit of research, after checking the vacuum hose for fuel(which would mean a bad regulator), if you put a pressure regulator on the rail then turn the key forward, it should jump right up to pressure of about 50 psi, if it gains pressure slowly then it's most likely a fuel pump problem. Then start the engine and remove the vacuum hose, if it jumps 5-7 psi, the regulator is functioning properly. After reconnecting the vacuum hose, put the engine under load and if the pressure drops more than 1 psi, your problem is most likely the fuel pump or a clogged fuel filter.

[rjgti]

It will still bleed off if the check valve on the pump is bad. You check the regulator by pulling off the vacuum hose to see if fuel is present.

good point, I forgot about that

[mp2008]

Well, im about 99% sure it's the fuel pump. Turned the key forward and heard it whining with some hesitation to it as well. Wasn't normal that's for sure. Reached up and took some pictures with my phone, I think it's safe to say it's the original pump... just to confirm before I order a new one, that is 2 electrical connections I see right? Which would make it the TCF version?