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Name the noise!

Hi. My 2001 gmc sonoma 2wd 4.3 is making a metallic kind of grinding noise.
You can hear it hear.

It drives fine.
It’s been happening more and more. Now it’s just about every time I start it.
It sounds like it’s coming from the bell housing but Im not sure. I used a stethoscope on it, but couldn’t hear it there.
Any advice/guesses would really be appreciated.

Wow, sounds a bit like a WWI airplane warming up. It does sound like it is a spinning part, but you might want to take it to a muffler shop first to make sure it’s not a loose heat shield? It’s hard to tell from the video’s sound. It also sounds similar to when I had a belt idler pulley bearing failing.

Sorry, probably not either.

Sounds to me like a bad lifter noise.That happened on my Chevy express some time ago before I junked it. The only solution was to replace the engine.

I checked the pulleys and tried to wiggle the heat shield. They all were fine. I think there is a good chance it’s the flexplate. I watched a video last night of someone with the same noise from the same truck thinking it was the flexplate and it went away when he replaced the starter…

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this is the video

I hope not. I cant do that. Thanks for the suggestion though.Ill check it out.

Try the stethoscope on the tensioner.

Well, yours does sound identical to that one in the video. That was one of my first suspicions- the bendix gear wasn’t fully retracting. Simple enough to verify. Some bellhousings have an inspection plate and that might allow you to see the starter snout without fully removing it but if not, not so bad a job. My other thought was a fan blade rubbing. But if you think it sounds like bellhousing area, this video lends a lot of credence to that possibility.

Sounds like the timing chain is rubbing.

Tester

It’s amazing that the man removed the starter to get at the flex plate and overlooked the loose bendix.

And if that shop were cleaned out he might have some room to work.

Thanks everyone

I took a stethoscope to where the starter and bellhousing meet and it’s definitely where the noise is at. How do i test to see if to see if its fully retracting? Do I just manually slide it back and forward? I’m pretty new working on cars,
Do you think theres a possibility that it has messed up the flexplate?

Congrats on probably finding the problem. About 4 minutes into the video he shows how his broke… the gear flops back and forth.

Remove the inspection plate and you can see all you want to see.

It turned out my bendix gear on my alternator not working properly. I believe it wasn’t retracting and rubbing my flex plate. Just a heads up for anyone having trouble getting their starter out in this year Sonoma, I had to take off the wheel well to get the wires lose from the starter. I used a socket extension and went in from the side and behind the front suspension. You There was no way I could get the starter out without taking the wires off an no wiggle room to get to the wires.

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good for you for figuring it out! and thanks for updating us

But what did you name the noise? The current noise in my truck is named ‘Fluffy’…

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“Lord Voldemort” aka he who must not be named.

Don’t want him coming back now do we.

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That would be your starter, not your alternator.

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Yep you’re right.