Electrical buzzing sound when trying to start

[2500HD-8.1L]

Greetings and happy holidays!

Thanks in advance for reading and sharing your experience.

SITUATION

MAKE: CHEVROLET
MODEL: SILVERADO 2500HD REGULAR CAB
YEAR: 2001
TYPE: PICKUP
ENGINE: GM VORTEC 8100 V8 8.1L (496 CID)
ACCESSORY PACKAGE: LS

ISSUE: The truck is in good shape for the age and has about 74,000 miles on it. Drove it all day yesterday making a thousand stops for last-minute Christmas stuff (good job there) and everything was fine - no weird sounds, trouble starting or other issues. Jumped in it this morning to go after some eggnog (disappeared last night somehow) and it would not start. I had bright lights, loud horn, and the door-open dinger was blaring as usual, but I got no crank at all. Instead all I could hear was this weird electrical buzzing sound.

 

Listen here: https://www.youtube.com/embed/eHYbQmNW7fg?rel=0&controls=0&showinfo=0

 

Tested the battery and it was at a full charge, so not that. But what?

 

Has anyone ever had, seen, or heard of this before?

 

[davester]

You hear this buzzing sound when you turn the key to the 'start' position? Where does the buzzing sound come from [inside the cab, or the engine compartment]? And what do you mean by doesn't start [engine doesn't turn over, or it spins but doesn't fire]?

[dewey05sd]

Sounds like your fuel pump. I don't hear anything weird

[davester]

yeah, finally listened to the sound. that sounds like the fuel pump.

[2500HD-8.1L]

To be clear, in the video the key is being turned all the way but the starter doesn't turn or even click at all - instead you just hear the recorded sound.

 

Dewey - My first thought was fuel pump, but it was just replaced less than nine months ago and the first one lasted thirteen years, I thought surely this one wouldn't be dead already. Besides, the weird thing that didn't fit with a fuel pump is that it actually doesn't crank - no starter sound at all. When it went out last time, you would hear the cranking and it was trying to start; it was more like when you are out of gas (of course). Now, it just sits there and you only hear the sound recorded above. So I'm getting from you that the fuel pump sound I recorded is always there and I usually don't hear it because of the starter cranking? If so, that would point to the starter being locked up or something.

[davester]

the sound is for the fuel pump, and it sounds like it's working fine. you can just hear it because there isn't the sound of the starter & engine to drown it out.

 

Yeah, now you have to figure out why the starter isn't working. I can't hear the sound of the solenoid that engages the starter [there should be an audible click of it engaging with the flywheel.

 

There's a starter relay in the under-hood fuse box. Check that it clicks when you turn the key.

 

If the relay clicks, then check that the starter is getting power [it's possible the power cable to it has failed after 15 years] and that it's getting the signal to engage/run.

[Silverado4x4]

Sounds like your starter took a dump, you could lightly tap on the starter with a hammer while someone is holding the key in the start position and see if it cranks.

[dewey05sd]

I agree with all that is said. Sounds like the fuel pump is functioning fine. Start investigating your starter. Check the fuse under the hood first and go from there.

[Formulabruce]

Ground on engine to cab RH side firewall, Battery ground wire ( or positive), OR a starter internal open due to some rust.

Tapping the starter with a drift pin and hammer is a good start, but its a ground issue most likely. Good luck@!

Its Funny , when its your own truck, you can easily loose focus on the simple things, I sure have... Merry Christmas!

[2500HD-8.1L]

Well, after getting the truck out where I could get to it, I tapped the starter a couple of times and it started right up - no dragging sticking or clicking. Let it sit for 48 hours in the freezing weather we've had here and bam - started right up without even getting in the truck. Absolutely no hint of an issue. So I'm guessing the problem was some combination of freak positioning upon completion of the last good start, combined with the 8 degree weather we had the night before it stopped working. Whatever it was it seem as good as new so I'm going too hang with it for a while. Thanks again for taking time to talk about my old truck - especially during the holidays. Hope everyone has a great 2016!

[Daddydave91]

So my 2003 gmc sonoma I blew head gasket and then finally got everything fixed and now back together. Before I took the head off to get fixed I was able to turn truck over and check compression. And now that it's fixed when I go to turn the key it doesn't do anything but make a loud electrical static type of noise. But it was turning over before I fixed it after it overheated. Does anyone have any idea what this could be. Thank's In advance