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Discussion Starter · #1 ·
So long story short, I had my door panels off for sound deadening and I drove the car for a bit with them off. Around 1500 and 1900 RPMs I would get a very loud and annoying resonance in the drivers door. I mistakenly assumed it was my new H pipe causing drone but when I opened the door during those RPMs the resonance immediately stopped.
I finished my sound deadening last night and reinstalled the door panel. The resonance at 1500 isn’t perceptible anymore but I can still hear it at 1900 although it’s much more muted. Now that I think about it that noise might have always been there and I just didn’t notice because I tend to drive with the exhaust mode in Track.
So how can you help? I was hoping a few of you with 2020+ models could take a few moments out of your day to see if you have the same issue. You can do this while parked. Rev your motor slowly to 2200 rpm or so in all exhaust modes and see if you notice a tone change anywhere around 1500 and 1900 give or take 100 RPM. If you think hear something then hold that RPM and open your driver door to see if it immediately disappears. I can definitely tell when the tone changes on mine and then goes back to normal around 2100 RPM. If you have the same resonance please let me know and also if your exhaust is modified or stock.
My end goal is to see if this is a design issue or if my issue is isolated. I have no idea what, if anything, Ford could do for this if it’s a design flaw.
Thanks in advance!
 

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Moderator/Admin Dude!
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The factory stereo has active noise reduction to get rid of unwanted frequencies like which you described. Opening the door disables the ANR.
 

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Discussion Starter · #3 ·
The factory stereo has active noise reduction to get rid of unwanted frequencies like which you described. Opening the door disables the ANR.
It’s definitely not the ANR. The door itself is resonating at those RPMs. I can hear it and feel it in the door skin and it stops as soon as I open the door. Window up or down doesn’t matter.
 
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Exhaust resonance is caused by the engine, exhuast, and/or body panels vibrating at incompatible frequencies. This can be compounded with changes in the exhuast itself or sound dampening.

There's a good chance your sound dampening is what's causing this to be more prominent.
 
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Discussion Starter · #5 ·
Exhaust resonance is caused by the engine, exhuast, and/or body panels vibrating at incompatible frequencies. This can be compounded with changes in the exhuast itself or sound dampening.

There's a good chance your sound dampening is what's causing this to be more prominent.
It was doing it before I added any sound dampening. It started (or at least became very apparent) once I removed the interior door panel. I had both sides off at the same time as I had the leather panels changed to match my new seat covers. Also, it’s happening regardless of exhaust mode and I’ve spoken to others with the same h-pipe and they have not noticed any drone or resonance. But the difference is they haven’t driven without the door panel installed.

Point is, I’m not asking for people to explain why they think it’s happening, I’m asking for people to volunteer a few minutes of their time to test my theory.
 

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If no one helps, I can try it tonight. Should I take it out in the open or were you in your garage?
 

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It’s definitely not the ANR. The door itself is resonating at those RPMs. I can hear it and feel it in the door skin and it stops as soon as I open the door. Window up or down doesn’t matter.
You have an aftermarket stereo… no?
 
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Discussion Starter · #8 ·
You have an aftermarket stereo… no?
Not yet, I’ve been doing all the wiring and prep work for the eventual install. But as it sits right now I’m still running the stock amp and speakers. I can’t imagine ANR would cause the door to resonate so badly…it’s worse than drone and it’s only the drivers door that does it.
 

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Discussion Starter · #9 ·
If no one helps, I can try it tonight. Should I take it out in the open or were you in your garage?
I don’t know if it matters either way but I appreciate the assist.
 

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It was doing it before I added any sound dampening. It started (or at least became very apparent) once I removed the interior door panel. I had both sides off at the same time as I had the leather panels changed to match my new seat covers. Also, it’s happening regardless of exhaust mode and I’ve spoken to others with the same h-pipe and they have not noticed any drone or resonance. But the difference is they haven’t driven without the door panel installed.

Point is, I’m not asking for people to explain why they think it’s happening, I’m asking for people to volunteer a few minutes of their time to test my theory.
Well, I would help test this, but I have a different motor and a completely modified exhuast. I can tell you this, I upgraded my exhaust in "phases" and definitely listened hard for anything I thought was out of the ordinary or that I didn't like. I never heard any odd resonance like the one you speak of. I know, different car/motor/ect. Just attempting to help. Which was why I posted my original comment, just a point of reference.
 

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So I tested it out in all modes with stock exhaust and the cabin was pretty quiet. Nothing out of the ordinary at those low rpms. Sorry man!
 
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+1 I checked and didn’t hear anything like you described however that little plastic cup that covers the hooks on the rear deck for strapping down a kids seat does rattle in my car. I’m fixing it now 😂 finally
 
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Discussion Starter · #15 ·
Thanks fellas. The more I think about the more I’m thinking the noise has always been there, I just noticed it more once the door panel was off.
On my way home from work I left my hand on the door and and could feel the vibration come and go within the same rpm ranges as before but the panel is muffling the majority of the sound. Maybe next time I pull them off to finish my audio install I’ll record the sound.
@HVCalTech has agreed to help me out by testing his once he pulls his door panels off for his sound deadening. Fingers crossed he doesn’t have it too cause I know it’ll drive him nuts like me!
 

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I drive in track mode unless the sun hasn’t come up and I’m leaving the Hood. Everything vibrates in mine 😂😂😂
 

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It’s definitely not the ANR. The door itself is resonating at those RPMs. I can hear it and feel it in the door skin and it stops as soon as I open the door. Window up or down doesn’t matter.
I remember reading a thread somewhere where the ANR was actually causing noise when somebody changed the exhaust. The factory system is designed to create out of phase noise to factory components. It’s possible the aftermarket changes are too much for it to cope with. It’s worth a try anyway. Just unplug the speaker in that door. Pretty sure you can unplug the microphone in the rear center of the headliner too.
 

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Two things to check even though you weren’t fielding solutions:
1) make sure that the door lock cable grommet is sitting firmly in its hole in the inner door skin. That damn thing can cause noise from the cable flapping against the door structure. I assume that you pulled the cable to open the door when you had the interior door panel off? That can easily pop that grommet out of the door panel. Ask me how I know.
2) if the door lock cable is not the culprit, check the door lock/latch/striker assembly.
 

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Discussion Starter · #19 ·
Two things to check even though you weren’t fielding solutions:
1) make sure that the door lock cable grommet is sitting firmly in its hole in the inner door skin. That damn thing can cause noise from the cable flapping against the door structure. I assume that you pulled the cable to open the door when you had the interior door panel off? That can easily pop that grommet out of the door panel. Ask me how I know.
2) if the door lock cable is not the culprit, check the door lock/latch/striker assembly.
It is seated correctly. I tugged on every cable and clip I could get my fingers on to see if something was loose. Just for 💩s and giggles I’m going to pull my speaker plug out of the amp and double check that the ANC isn’t causing some weird output from the speakers.
 
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