2000 Silverado 5.3L won't start, any ideas?

[Coiled]

- very few miles driven in the last 14mo since 2018 inspection / registration
- battery was dead
- 10amp battery charge for 1.5hrs, then the motor turned over strong for 4 - 20second tries with @ 1min pause between the pair
- I did not hear the fuel pump prime during any ignition ON but between the door dinger and home A/C nearby, I may have missed it​

I installed a new fuel pump @2005 so that can't be it
Can a parts store test the cubed, 4 prong relay(?) in the fuse block area?

 

[baboon]

Computer went out with dead battery.

 

[Bozz10mm]

Fuel pump.

 

[GasGuzzler]

Fuel pump. 2000 is about the worst year for GMT400 fuel pumps and if you got it at the parts store I'm surprised it made it this long. Today's unleaded gas goes bad sitting a lot faster than in days past but it should at least try to run. You can shoot a little carb cleaner into the throttle body and see if she tries to start or you can beat on the bottom of the fuel tank while someone cranks the engine and hopefully the fuel pump motor will free up. Fuel pump fuse is PCMB underhood if memory serves. Be advised this model of pump requires a new harness connector be spliced in.

 

[Mikewood]

I would start with a new battery. Then look at a dry rotted fuel pump. Check your fuel line to see if it is plugged. Spray a little starter fluid into the throttle body and see if you can get it to sputter.

 

[TexasRedneck]

If you stored it without starting and without preservative in the gas, you are in for a MAJOR fight to get things going again without a major $$$ hit. Today's fuels with the ethanol are an absolute NIGHTMARE to any fuel system AND the fuel lines! 90% chance that your fuel pump is toast - regardless of when it was last replaced. The battery.....yeah, IMO it should be replaced. I'd drain every last drop of gas in that tank and replace it with about 6 gallons of fresh NON-ethanol gasoline, and add about a half can of SeaFoam to the gas.......and pray.
Once the gas is replaced and the new fuel pump installed, spray some ether into the intake and crank it with every good luck charm/talisman you have, chanting appropriately to the Gds of The Engines to let it fire.
My "backup" truck gets non-ethanol gas any time I fill it, simply because I don't know when I'll be using it again (it's often months), along with fuel stabilizer. It's just cheap insurance.

 

[Brains]

If you have a test light or a volt meter (or can rig something up), pull the fuel pump relay and put the light between terminals 85 and 86 in the socket. You should get 0V key off, 12V key on for a couple seconds while the PCM primes the pump, then back to 0V. This will verify the PCM is fine (it will be).

With the relay still pulled, bypass it with some 18ga. wire, see if the pump starts running to rule out the relay. Jump pins 30 and 87 in the socket.

(nb. I didn't draw this, just found it to show the wiring diagram of the relay socket.)

If you see a spark, but no pump whirring, it's the pump.

If you don't see a spark, check the fuse (closely followed by probably another blown fuse, and a new fuel pump)

If everything checks out so far but still no start, check for fuel pressure by pulling the test port cap on the fuel rail and depressing the schraeder valve. *WARNING* fuel will potentially spray out, take appropriate safety measures No fuel might mean a clogged fuel filter, line popped off the fuel pump inside the tank, line split in the tank.

If you have fuel pressure, might be time to pull trouble codes and see if there's anything stored. If you don't have a code scanner, try pulling a plug wire and setting up a gap to ground with some wire to test for spark. No spark means the PCM isn't enabling engine start, do you have a security light flashing (not solid) on the dash? Could be the little resistor pill in the key not making good contact with the ignition switch.

 

[Vaquero]

Fuse. I helped a buddy drop a fuel tank and swap the pump out.
Put it all together. Nothing. Checked the fuse. Yep. Blown.
Never knew if the old pump was really bad or not. Heh.

 

[oldag]

Fuse. I helped a buddy drop a fuel tank and swap the pump out.
Put it all together. Nothing. Checked the fuse. Yep. Blown.
Never knew if the old pump was really bad or not. Heh.

Pretty good definition of frustration.

 

[Brains]

Never knew if the old pump was really bad or not. Heh.

It probably was, fuses don't blow for no reason.

 

[1911'S 4 Me]

I would start with the $10 inline fuel filter, frame mounted under drivers side door. My '96 died while driving, changed the filter,that was MY problem. There can be many reasons.

 

[Renegade]

- 10amp battery charge for 1.5hrs, then the motor turned over strong for 4 - 20second tries with @ 1min pause between the pair​

Does not matter how much amp you charged it with or how long. Whether it is fully charged is what matters.

From your description, it sounds like your battery is not fully charged. It is common to have a enough Voltage to turn over the starter, but not enough to pressurize the fuel rails.​

 

[Brains]

Before you crank (key in on position, not yet turned to start) the PCM will prime the fuel system and bring it up to pressure. During this time you would, if everything is working properly, hear the pump turn on for a couple seconds and turn off. The fuel pump takes a lot less current to run than the starter motor, so if it'll crank, it'll pump.

 

[Southpaw]

Did ya check the tail pipe?

 

[Vaquero]

Did y'all read the OP?

 

[skfullgun]

Any update?

 

[GasGuzzler]

The 2000 has a fuel tank module not a pump on a sender like ten years before so there is very little likelihood a hose split (like the 96-99 version). When a pump wears, the motor gains resistance which will eventually blow the fuse. Most times though the pump stalls before it blows a fuse. The starter is by far the highest amperage draw device so if the engine turns over, there's enough juice to run the injectors.

I've installed Airtex and other parts store brand pumps in these trucks that didn't make it out of the parking lot.

 

[Coiled]

Which pump manufacturer(s) do you recommend GasGuzzler?

Any update?

Nah, temp was just below 100 yesterday until the skies fell out so I didn't work on my standby vehicle.

One thing is for sure, we don't have a spastic eyed black dude roaming the hood with a hand full of nanners.

I do appreciate all the input guys.

 

[GasGuzzler]

Bite the bullet and get the OEM replacement. Fuel pumps, ECM's, and mass airflow sensors from the aftermarket are generally trash.