Hissing Noise When Going Over 70 MPH








It can be from outside or it can be from inside, from /engine /brakes /suspensions /vents /dashboard /undercariage /prop. shaft /exhaust /blower fan ....
It's not easy to pin-point the source




Last edited by pierrejoliat; Sep 19, 2025 at 04:39 PM.




Mine has this issue but I ignore it but did test with masking tape and noise went away.
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HVAC evaporator with low R134a charge can make hissing noise, its from the TXV.
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Other wind noise which may enter the car is when the vent flap of HVAC is in FRESH AIR MODE..... but since the air box above the battery for HVAC is on purpose there
to trap and discharge rain water plus 2 of 90 degrees airflow diversion and the windshield wiper cowling design does not force air into the HVAC system, this condition is rare unless something there is blocked or obstructed.
My new in mid 2023 windshield wiper cowling vent holes has fine wire mesh, old one of 2014 was diamond shape opening without fine wire mesh.
I wonder if the wire mesh get clogged plenty, will there be wind sound ?
Old windshield wiper cowling vent holes, no wire mesh
New version has wire mesh
.
Only HVAC fresh air vent being open , is the way any significant amount of air can enter the car AC air handling system aka your AC mid vent.
Good luck on the search......
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