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Weird ass electrical beep/buzz

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Old Oct 1, 2016 | 12:19 AM
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Default Weird *** electrical beep/buzz

I have no clue what is going on here. Someone smarter than me please help.

Video one I can unplug one of the coils and the beep/buzz stops. After a certain amount of time it stops. Then I realized it matches a wried *** thing the wideband is doing video two. Sorry didn't realize the alarm next door was drowning it out but you can still hear the beep/buzz.


Old Oct 1, 2016 | 07:40 AM
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The AEM gauge does buzz a little, I can definitely hear on my quiet workbench, although I don't expect to be able to hear it in a car.

Does the engine bay noise stop if you disconnect the idle valve?
Old Oct 1, 2016 | 10:01 AM
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Originally Posted by Reverant
The AEM gauge does buzz a little, I can definitely hear on my quiet workbench, although I don't expect to be able to hear it in a car.

Does the engine bay noise stop if you disconnect the idle valve?
No idle valve
Old Oct 3, 2016 | 03:58 PM
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The PWM heater for the AEM puts a **** ton of noise on the ground/power for the car. It is about 1A worth.

Your coil is ringing from that (coil of wire = electro magnet = speaker). My head unit did the same thing in mine. The actual head unit, with all the speakers disconected, would ring.

Connect a 2200uF (or bigger) 25V (or more) capacitor between the power and ground lines for the AEM. It should greatly lower the noise.
Old Oct 4, 2016 | 10:34 AM
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Originally Posted by x_25
The PWM heater for the AEM puts a **** ton of noise on the ground/power for the car. It is about 1A worth.

Your coil is ringing from that (coil of wire = electro magnet = speaker). My head unit did the same thing in mine. The actual head unit, with all the speakers disconected, would ring.

Connect a 2200uF (or bigger) 25V (or more) capacitor between the power and ground lines for the AEM. It should greatly lower the noise.
I found a missing ground wire that goes from the coil plug to the intake manifold. The tone is now barely audible and from what you said sounds like that's ok.
Old Oct 4, 2016 | 10:38 AM
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Missing ground there would do it too. Although the AEM is still dumping ton's of noise. I would reccomend the cap anyway to make sure itndoesn't cause any problems with other sensors or whatnot.
Old Oct 4, 2016 | 10:56 AM
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Originally Posted by x_25
Missing ground there would do it too. Although the AEM is still dumping ton's of noise. I would reccomend the cap anyway to make sure itndoesn't cause any problems with other sensors or whatnot.
Thanks I will get 2 caps and install them.
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