Whistle Noise only at 65-75MPH (1 Viewer)

[heritage05]

Anyone get this noise and know the solution? It’s coming from behind the dash, sounds like a reed noise (musical reed) and is definitely caused by outside air being forced through something that is likely vibrating to cause noise, like a reed vibrates or if you put a pice of grass between your thumbs and blow. Only happens at 65-75mph range and doesn’t happen when it’s raining. When I had my console apart to install new 6x Tesla screen I took it for a drive to see if I could better locate the exact area of noise but no luck.

 

[Mars06LC]

Don't have an answer but there are only so many places air can be coming into cabin. My first thought is around the windshield since it's most exposed. Has the windshield ever been replaced? Shoddy work can lead to rust on the mounting surface which could create a gap for air.

I doubt there's enough airflow in the engine bay to cause a whistling through the firewall grommets, although I recall threads about cold outside air coming in from passenger floorboard and I think it was due to a firewall grommet. But, you saying its from behind the dash makes this more likely. Also, there is a path for the HVAC air intake that is passenger side cowling (under hood, above AHC tank and airbox) down through the HVAC behind glove box, but that intake is covered by hood. Maybe clean out blower motor and cowling under hood above firewall for leaves or sticks, though doubtful the cause.

 

[merbesfield]

My 100 also does this and I’m guessing it’s a bad windshield installation but don’t know for sure. Very irritating. It was there when I bought it and haven’t done anything yet since I plan on installing a new windshield at some point. Let us know if you figure it out.

 

[JunkCrzr89]

Unrelated, but my exhaust whistles like a really terrible turbo between 2300 and 3200 RPMs. Wife hates it so I lovingly decided not to fix it.