Squealing At 75mph Coming From Dash

Ok,I have a 07 corolla and recently took it on its first road trip to the UP of Michigan. I've never taken it up over 70 but I did up there. I was driving about 75 and it seemed if the wind was just right or a semi passed at a certain point, there would be this really loud squeal coming from under the dash on the passenger side. It sounded like air being blown through a small opening between two pieces of plastic. It did it alot but only if I reached about 74mph+.

Or perhaps there really is a hole somewhere in the engine firewall, where air, being forced against the firewall from the engine side, is squeezed through. Or perhaps air from the air from the climate control intake (usually at the lower edge of the windshield) is hitting some sort of hole or vent gate that just happens to make noise. Perhaps take a peek under the dash or have a friend listen to the area under the dash while you drive at 74+ mph.

Just my 2 cents, here.

Is your window gasket out of place, or your window not rolled up completely? Sounds can be tricky in a car even though they sound like theyre coming some place else is why I ask. If it is indeed under the dash then maybe the ac recirculator door is not shutting completely against the vent. Do you hear the noise while in both recirculate and non recirculate mode?

Agreed that a bad window gasket can do it. A roof rack can do it. Check for anything loose around the windshield and both side mirrors. Even the smallest piece of loose gasket or tape can buzz/squeal loudly in the wind at highway speeds.

Also make sure nothing is lodged in the front grill, maybe up against the radiator, or somewhere underneath in the front suspension. I've seen pieces of plastic bags get stuck in these places and squeal/whistle very loudly at highway speeds.

Any of the above might sound like it's coming from underneath the dashboard depending on the acoustics inside the car.

The next time it happens try turning your A/C blower off. It could also be a piece of foam that has shaken loose in the duct work or the A/C may have excessive condensation.

The speed / semi passing observation may just be a coincidence.

My friend has an '05, he had a similar problem which occurred at highway speeds, it was repaired under warranty. Something to do with the cabin air intake. Hope this helps.

Don't drive over 70 MPH.

Ok,I have a 07 corolla and recently took it on its first road trip to the UP of Michigan. I've never taken it up over 70 but I did up there. I was driving about 75 and it seemed if the wind was just right or a semi passed at a certain point, there would be this really loud squeal coming from under the dash on the passenger side. It sounded like air being blown through a small opening between two pieces of plastic. It did it alot but only if I reached about 74mph+.

Hmmm....So the squealing continues as you drive above 74 miles . . .? The speedometer cable can make a loud squeal, especially if gear oil is being forced up the cable. usually one will see oil leaking from under the dash, but not always. In some cases (as in my case) it made a loud noise, and the gauge started fluctuating.

 

Or perhaps there really is a hole somewhere in the engine firewall, where air, being forced against the firewall from the engine side, is squeezed through. Or perhaps air from the air from the climate control intake (usually at the lower edge of the windshield) is hitting some sort of hole or vent gate that just happens to make noise. Perhaps take a peek under the dash or have a friend listen to the area under the dash while you drive at 74+ mph.

Just my 2 cents, here.

Cars don't have speedometer cables anymore. They have electrical sensors to determine speed called vehicle speed sensors. They are part of an electrical circuit that makes the speedometer work, so there goes any theory involving a speedometer cable.

He may be right about forced air making the noise.

I've had this when driving against a strong wind. I would describe it more as a whistle. My best guess is that it is the wind blowing across the cabin air intake just in front of the windshield wipers. It is like blowing across the top of a beer bottle to make it whistle. I don't have a solution. It's only happened a couple of times when the wind is just right and strong enough.

I've had this when driving against a strong wind. I would describe it more as a whistle. My best guess is that it is the wind blowing across the cabin air intake just in front of the windshield wipers. It is like blowing across the top of a beer bottle to make it whistle. I don't have a solution. It's only happened a couple of times when the wind is just right and strong enough.

Okay, I'm glad to find this, because I've been having this problem in my 06 LE for about 2 years now. I live in a more rural community east of Denver, so I'm on the highway all the time - 75mph speed limit. As soon as I hit about 74 or 75, I get the really high-pitched fairly loud buzzing (or "squealing") sound, too. On some days it doesn't happen at all, on others it's constant - it seems to depend on the wind direction, too, rather than just my speed. The other night, my fiancé was pushing in certain spots toward the middle of the dash to see if it would help. Sometimes it did, other times it made it worse.

To answer some of the previously posted questions:

--This only happens at 74-75 mph and above. It's never happened (to me) at slower speeds.

--All of the windows are completely rolled up when this happens. If the windows are cracked open (maybe an inch, or so), it doesn't happen. Typically, though, when I'm at that speed, the windows are closed up.

--The buzzing happens regardless of whether the heater or A/C is on or off.

--I recently did an oil change, and got a good look at the inside/underside of the grill and front suspension. Except for the insect graveyard behind the grill and on the radiator, nothing is stuck (e.g., a plastic bag) that I could see that would cause this kind of noise.

I'll check the windshield gasket seal to see if maybe that's the problem - I have a few rock chips anyway, so it could stand to be replaced.

If anyone else has any other suggestions, I'm happy to look and try them. I'd really like to get this fixed.

I'll post progress and/or the solution!

Edit: I just saw oagly's post in the "Dashboard Vibrations" thread. I'll check out the brackets behind the glove compartment, too. That's good to know.

And look at this!! I dug this up in the "2005 Corolla Wind Noise" thread:

http://www.netwire-s...com/pics/72.pdf

PERFECT!!! That makes complete sense! Looks like I'm getting a new windshield, and having them re-seal the molding!