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Funny buzzing sound...

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Old 10-08-2015, 09:55 AM
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Funny buzzing sound...

So while teaching my 15 year old to drive I get a little time in the passenger seat. I keep hearing this intermittent electric buzzing sound and it seems to coincide with the gas. No that I've noticed it I hear it when I drive the car. It seems when I am off the gas to slow down then when I give it gas again to accelerate I hear this buzzing for a couple seconds then it stops.

It sound like it's coming from under the dash on the passenger side kind of above where the ECM is mounted. Hard to describe the sound but I'd say it sounds like a little electric motor or something that vibrates.

Any ideas what I'm hearing?
Old 10-08-2015, 11:44 AM
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Re: Funny buzzing sound...

Sure it's not coming from a speaker? I've had electrical noise come through the speakers. Just a guess.
Old 10-08-2015, 02:16 PM
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Re: Funny buzzing sound...

Originally Posted by aliceempire
Sure it's not coming from a speaker? I've had electrical noise come through the speakers. Just a guess.
I don't think so. Never heard anything like it come from a speaker but I will turn the radio off and try it.

Really seems to be triggered by the gas pedal. I'll check it out with the radio off.
Old 10-08-2015, 02:31 PM
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Re: Funny buzzing sound...

I'm reaching waaaaaayyyyyyyyy out there....but... EGR Solenoid on the other side of the firewall operating and buzzing when open/closing EGR??

Yeah, I didn't think so.

Flux Capacitor charging up? Joke

, good one if it's not the speaker.
Old 10-08-2015, 02:34 PM
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Re: Funny buzzing sound...

Does it buzz when it operates? If so, that could be it. It's in that general area. Would it be opening the EGR when the gas is applied? It only buzzes for about 2-3 seconds then stops..?
Old 10-08-2015, 02:54 PM
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Re: Funny buzzing sound...

I tested a few that buzzed. Normally they shuttle open or closed depending on when demanded.

IIRC when cruising it's opening and closing as needed. On decell, I think its (EGR Valve) is commanded closed.
Old 10-08-2015, 02:57 PM
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Re: Funny buzzing sound...

Sounds like I can't check this at idle with the hood up? Am I going to have to climb under the hood while the boy drives??
Old 10-08-2015, 02:58 PM
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Re: Funny buzzing sound...

BTW...Solenoids will sometimes "buzz or Chatter." It's the plunger in between the magnets in the case of the solenoid. Slop, so to speak
Old 10-08-2015, 03:02 PM
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Re: Funny buzzing sound...

Chatter is a VERY good description of what I am hearing. Bob, you da man! I bet that's it but still gonna turn off the radio next time we drive it..

So, just to confirm there is nothing inside the dash area that would make a noise like that?
Old 10-08-2015, 03:05 PM
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Re: Funny buzzing sound...

I was waiting for that!
Good one! reminds me of a time when I was young. Friend had me drive his 69 Road Runner on a back road after we installed his engine. No hood, no timing light, and Rick sitting on the inner fender adjusting the distributor while going 40 or so.

Idea though. Tape a piece of tubing around the area of the solenoid and run it inside through the window and then have your son drive. Place tubing up to your ear and listen. You'll def hear it if that's it. Just an idea
Old 10-08-2015, 03:07 PM
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Re: Funny buzzing sound...

Originally Posted by 86IROC112
Chatter is a VERY good description of what I am hearing. Bob, you da man! I bet that's it but still gonna turn off the radio next time we drive it..

So, just to confirm there is nothing inside the dash area that would make a noise like that?
Power antenna relay, computer, CC Module right behind that panel. That's all I can think of
Old 10-08-2015, 03:12 PM
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Re: Funny buzzing sound...

Yeah, I did some really dumb things when I was young too. I hope my kid doesn't but probably will...

Thanks Bob, I'll try the hose idea...brilliant..
Old 10-08-2015, 03:23 PM
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Re: Funny buzzing sound...

Good luck. Keep us posted.
Old 12-21-2016, 06:37 PM
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Re: Funny buzzing sound...

I think I have that same issue. I hear a steady buzzing-ish sound coming from somewhere in the dash. Mine is in the same area as described by the OP. I have had the kick panel off and it is not coming from the power antenna relay area. It is from deeper in the dash. It is definitely not speaker or stereo related.

It is not the EGR solenoid. I can see where you'd hear buzzing from one on the bench, but to hear it inside the car on the other side of the firewall over the engine sounds would be a bit of a stretch since it would be unbearably loud outside the car.
Old 12-21-2016, 06:44 PM
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Re: Funny buzzing sound...

Typical things that do that in relation to pressing the gas, are the HVAC control diaphragms.

When the gas is pressed, vacuum goes away, then comes back at other times. If the check valve and reservoir aren't plumbed properly, the doors will move in response to that.
Old 12-21-2016, 08:11 PM
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Re: Funny buzzing sound...

That was my first thought as well. Try disconnecting the vacuum source tube under the hood and see if it goes away.




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