Easy and effective low frequency fix

[Bp25]

I admit that I am more sensitive to annoying noise and ear pressure in the car, but MY is far from a good built car. I have driven Lexus vehicles for 15 years and never had to put sound deadening pads because the manufacturer already had it there. On the other hand, Honda vehicles seemed like tin cans to me, so I avoided them, but millions of people drive them with no issues.

I didn’t post here to pick a fight. I bought the car for powertrain performance and am very happy with that. I knew the software has issues and I can live with it. The buffeting and noise issues were something that I could not live with, so I tried almost everything that people in this forum had success with, and just wanted to report what worked for me. If someone is happy with the car as is, nothing wrong with that either. But it’s not a car built by luxury car standards, though it’s priced like one.

 

[WhiteWi]

I admit that I am more sensitive to annoying noise and ear pressure in the car, but MY is far from a good built car. I have driven Lexus vehicles for 15 years and never had to put sound deadening pads because the manufacturer already had it there. On the other hand, Honda vehicles seemed like tin cans to me, so I avoided them, but millions of people drive them with no issues.

I didn’t post here to pick a fight. I bought the car for powertrain performance and am very happy with that. I knew the software has issues and I can live with it. The buffeting and noise issues were something that I could not live with, so I tried almost everything that people in this forum had success with, and just wanted to report what worked for me. If someone is happy with the car as is, nothing wrong with that either. But it’s not a car built by luxury car standards, though it’s priced like one.

Nothing is prefect even Lexus.

 

[Johnny Vector]

Nothing is prefect even Lexus.

Of course. I mean, it's not Lexus Prefect, it's ... Ford Prefect.

I'll show myself out.

 

[FumelessCamper]

I am wondering if anyone has tried putting acoustic tiles on the inside of the panoramic roof? Stick on floor carpet tiles on the ceiling to absorb sound?

 

[Sudsington]

I admit that I am more sensitive to annoying noise and ear pressure in the car, but MY is far from a good built car. I have driven Lexus vehicles for 15 years and never had to put sound deadening pads because the manufacturer already had it there. On the other hand, Honda vehicles seemed like tin cans to me, so I avoided them, but millions of people drive them with no issues.

I didn’t post here to pick a fight. I bought the car for powertrain performance and am very happy with that. I knew the software has issues and I can live with it. The buffeting and noise issues were something that I could not live with, so I tried almost everything that people in this forum had success with, and just wanted to report what worked for me. If someone is happy with the car as is, nothing wrong with that either. But it’s not a car built by luxury car standards, though it’s priced like one.

My belief is that Teslas are priced the way they are because of the battery and efficiency technology (as well as the last year's price increases due to overwhelming demand and part/chip shortages). They do include some premium/luxury features, but it really isn't a luxury vehicle overall.

The difficulty for Tesla, and buyers who are cross-shopping other EVs, is that the buyers will compare (whether it's Tesla's intention or not) the price of Teslas to EVs that have more and/or better luxury features, but may not match the battery or efficiency tech (or the Supercharger network). It's a trade-off that is definitely worth examining. I love my Model Y for me, but I also think my uncle, who bought an e-tron for local drives and commuting, got the best EV for him and his wife (who are both used to Audis/Infinitis).

I'm curious where Tesla will try to position themselves as batteries get cheaper. At the mid-range premium price point with similar feature set as they have now, or maintaining their current price point while improving and increasing their luxury features.

 

[Sudsington]

Yep. I think quite a few of us have done ride tests with service centres with usually the outcome of "I can't hear anything wrong"

Nope. Tesla acknowledged the problem in a TSB in Asia and allegedly in the USA as well but their "fix" did not seem to fix the issues for those that had it done (a little plastic piece in the hatch opening and an extra rubber seal).

Also 32 pages on the Ear Pain thread is a good indication.

There's a whitepaper on this topic with EVs and this problem is not specific to Tesla (I forget but it's buried in the ear pain thread somewhere). Audi's etron has it worse than Tesla.

If you can't hear it, it's simply because you can't hear it, not because it's not there. It's there on every stock Model Y. Some of us have better hearing to our own detriment I guess haha.

I took a ride in my neighbor's August 2021 build Model Y, and didn't hear any of the buffeting and booming issues that I had with my car. They didn't even adjust the hatch stops apparently. I also asked my cousin who has a Y, and he hasn't noticed anything that I described to him (but he's in another state, so I can't force him to give me a ride to test it out hah).

My theory is that some of the hatches sit loosely on the hatch stops and rubber trim, because of some inconsistency in the tolerances of the hatch hinges, latch, and the hatch itself. Whereas other Model Y hatches are tightly held against the hatch stops and trim, because of the hinges and latch arrangement for their hatches. So it may be significantly better in some cars vs others, which could make it more difficult for techs and engineers to fix the inconsistent issue. That's just speculation on my part, of course.

 

[ilovecoffee]

I took a ride in my neighbor's August 2021 build Model Y, and didn't hear any of the buffeting and booming issues that I had with my car. They didn't even adjust the hatch stops apparently. I also asked my cousin who has a Y, and he hasn't noticed anything that I described to him (but he's in another state, so I can't force him to give me a ride to test it out hah).

My theory is that some of the hatches sit loosely on the hatch stops and rubber trim, because of some inconsistency in the tolerances of the hatch hinges, latch, and the hatch itself. Whereas other Model Y hatches are tightly held against the hatch stops and trim, because of the hinges and latch arrangement for their hatches. So it may be significantly better in some cars vs others, which could make it more difficult for techs and engineers to fix the inconsistent issue. That's just speculation on my part, of course.

Hrm. The only two other Y's I've ridden in both had this issue.

 

[watsongrg]

Note that several of part numbers posted in this thread are incorrect. The correct diameter is 3/4", not 1/2".

As you've probably guessed, I slipped two of these PVC covers over my outer (next to the taillights) hatch stoppers today, after sanding the insides of the PVC covers with my Dremel so the OEM stops would fit all the way inside. I didn't have to cut the new PVC parts because I removed the OEM rubber nut from the OEM stopper before slipping the PVC parts over. Then I made sure all four of my stops were in tight contact.

I'm not sure I can notice any improvement, to be honest. Textured pavement is still bad. Everywhere else is still fine. My only guess is I made a mistake by fitting the PVC covers all the way over the OEM stops. That means the OEM part of the stops is unscrewed some distance from the vehicle, which may allow compression and/or play. In other words, it may be important that the OEM stop is screwed in all the way.

you are correct it’s the ¾”, item 2118, at HomeDepot. Otherwise what I pictured is what it looks like.

But, if you removed the stock plastic “nut” from the rubber bumper, you did it wrong and that could be why you didn’t have success. Just slipping the PVC end-cap over the rubber bumper isn’t providing the rigidity that having it butted against the stock plastic nut does.
I would encourage you to do it like I and MY-Y described and pictured as examples.

I couldn’t be happier with the fix.

 

[watsongrg]

Hrm. The only two other Y's I've ridden in both had this issue.

Yes. I think they all have the issue, just some people don’t perceive it.
My wife said she noticed nothing unusual, yet it was driving me nuts. My daughter noticed it too.
Also took a buddy for a ride, and kept asking him if he felt the ear and sinus pressure, and booming over pavement cracks and bumps. He though I was joking because he didnt feel it either.
But plenty of people do feel it.

 

[watsongrg]

The huge and heavy rear hatch of the Model Y is not nearly supported enough, because it doesn’t use sturdy supportive bumpers or stops.
It uses flimsy rubber bumpers that are spirally cut (a further lose of rigidity) and are simply twisted into the hatch.
No support no rigidity. That’s why the hatch is bouncing and causing pressure waves.

In contrast, see the hatch stop on a Chevy Volt. Large, solid, rigid support, bolted to the hatch with a bracket.
Thats the way it’s done …..

Come on Tesla, step up and design a rigid, supportive hatch support.

1

 

[Johnny Vector]

I am wondering if anyone has tried putting acoustic tiles on the inside of the panoramic roof? Stick on floor carpet tiles on the ceiling to absorb sound?

Sadly, that won't help with the low-frequency issue people are talking about here. Buckle in, here comes an acoustics primer!

The way sound absorbent material works is to interrupt the flow of air in the sound wave. Where the air interfaces with a solid surface, there is no air motion (a node) and maximum change in pressure (an antinode). 1/4 wavelength away from the surface is the opposite: an antinode of motion and a node of pressure. So to absorb a particular frequency you get the best results with your absorbing material 1/4 wavelength from the surface. The efficacy goes down as you move toward a node in air flow, e.g. right next to the surface.

So, how far is 1/4 wave? The peak of the resonance in question (from other posts here) is 41 Hz IIRC. (Amusingly, this is the low E on a bass.) Sound travels at 1100 fps, so the wavelength at 41 Hz is 27 feet. So to get optimum damping you want your absorbent material 6-7 feet away from the surface. Oops.

Now, you do get some damping even if you're closer than optimal. In my old home studio, I got enough reduction of the first room mode (which was A#, 43.4 Hz, 25' wavelength, making e.g. Johnny B. Goode sound awful in the original key) with fiberglass panels 1-2' from the corners. But the thickness of acoustic tile just isn't enough to help with these low frequencies.

 

[Johnny Vector]

Sadly, that won't help with the low-frequency issue people are talking about here. Buckle in, here comes an acoustics primer!

The way sound absorbent material works is to interrupt the flow of air in the sound wave. Where the air interfaces with a solid surface, there is no air motion (a node) and maximum change in pressure (an antinode). 1/4 wavelength away from the surface is the opposite: an antinode of motion and a node of pressure. So to absorb a particular frequency you get the best results with your absorbing material 1/4 wavelength from the surface. The efficacy goes down as you move toward a node in air flow, e.g. right next to the surface.

So, how far is 1/4 wave? The peak of the resonance in question (from other posts here) is 41 Hz IIRC. (Amusingly, this is the low E on a bass.) Sound travels at 1100 fps, so the wavelength at 41 Hz is 27 feet. So to get optimum damping you want your absorbent material 6-7 feet away from the surface. Oops.

Now, you do get some damping even if you're closer than optimal. In my old home studio, I got enough reduction of the first room mode (which was A#, 43.4 Hz, 25' wavelength, making e.g. Johnny B. Goode sound awful in the original key) with fiberglass panels 1-2' from the corners. But the thickness of acoustic tile just isn't enough to help with these low frequencies.

Oh geez, I totally screwed up the last parenthetical. Low A# is 58.3 Hz, 19' wavelength. Everything else is still absolutely true, I promise hope.

Gotta get the band back together before I totally forget how music works.

 

[Noflash]

I think the confusion is caps versus plugs. Plugs go in the pipe. Caps go over the pipe. 3/4" plug and 1/2" cap work. The Lowe's cap has a rounded end, so might not work as well.

 

[Noflash]

I have solved the low frequency issue with my car. I had a 41 Hz standing wave that would come and go. It wasn't good. If the hatch bumpers are loose, a crazy subsonic buffeting occurs. I'm talking about the annoying rumble that is still there when the bumpers are properly adjusted.

To keep it brief, I placed my phone running the "spectroid" spectrum analyzer on my dash. I then went aound my car, thumping different spots with my hand to see which area(s) caused a 41 Hz resonance. Bottom line, pretty much all of the low frequency is from the hatch. Center glass and center of the metal has resonances at 47 and 50 Hz. The corners where the upper bumpers hit are the 41 Hz culprit.

...

The 47 and 50 Hz sounds are not annoying to me. If I feel inspired, I may make rigid stops for the bottom two.

Bottom line... after careful analysis, I have made my car much more enjoyable for very little cost.

Someone tell me what I am doing wrong, because I see no improvement in the booming. Rubber is screwed all the way in, OE plastic nut it tightened against the metal, pvc cap is sanded until the hatch closes. I did the paper test and there is a rigid connection. Boomy as ever.

 

[MY-Y]

My guess is that there is still a hair of clearance between your caps and the car when closed. The hatch doesn't have to move much to make a lot of noise. Mine are preloaded some. I suggest putting a chair leg felt pad on the bottom of each to test. You may need to push on your hatch a bit to get it to latch for this test.

 

[Bp25]

See my post #49 above. Yours sounds like mine and tube insertion is needed.

 

[Noflash]

My guess is that there is still a hair of clearance between your caps and the car when closed. The hatch doesn't have to move much to make a lot of noise. Mine are preloaded some. I suggest putting a chair leg felt pad on the bottom of each to test. You may need to push on your hatch a bit to get it to latch for this test.

I did the paper test on both, so there is no space. Not sure what you mean by "preloaded", but I'll try the felt.

See my post #49 above. Yours sounds like mine and tube insertion is needed.

I tried this first - 2 different sizes of tubing. Responded in the Ear Pain thread. It's definitely firm. There is increased gap and the hatch "pops" upon opening.

 

[PecuniaNonOlet]

Two theories.

1. Your boom is not coming from the hatch. My vehicle was missing standard insulation. Adding it helped a lot, more than anything I've done to the hatch so far. But I still get plenty of boom on textured pavement. I will be trying the tube insertion and rigid hatch stops over the next few days. If I still have boom on textured pavement then I will be in the same boat as you with my hatch.

2. You are driving over a type of textured pavement that others (except maybe me) here have not encountered. Unlikely, yes, but I want to put it out there because you could fool me into thinking I have a quiet car for quite a while now if you know which roads to avoid. Roads in my neighborhood for example are fine. But then I head out to some groovy textured pavement and the boom is amazing.

 

[Bp25]

I did the paper test on both, so there is no space. Not sure what you mean by "preloaded", but I'll try the felt.

I tried this first - 2 different sizes of tubing. Responded in the Ear Pain thread. It's definitely firm. There is increased gap and the hatch "pops" upon opening.

After inserting tube, I actually backed off the rigid stops a little so that the hatch rests on the gasket and not on the stops. If the catch holds the hatch so tight that it pops when opening, it unlikely that the hatch is moving anymore. As Pecunia mentioned, the problem is probably lack of insulation.

 

[watsongrg]

Someone tell me what I am doing wrong, because I see no improvement in the booming. Rubber is screwed all the way in, OE plastic nut it tightened against the metal, pvc cap is sanded until the hatch closes. I did the paper test and there is a rigid connection. Boomy as ever.
View attachment 771771
View attachment 771772

Those look Good. But MY-Y is probably right, they need to be just a bit bigger.
My original ones worked great, but i obsessed with whether they were too big and eventually sanded them down another mm. or so. Eventually the boominess began to return and I had to make new ones again to the original size. Now the boominess is gone, with slightly larger stops. I also reduced my tire pressure to 37psi.
Rides and sounds like a normal car 95% of the time. Most importantly, no ear pressure or sinus discomfort.