I've had my car for about a year now. It had a frontal collision in 2017 when it had 7K+ miles on the clock. Left fender, bumper, grill, and hood were replaced. No air bags were deployed. When I go over 70 MPH, I get a noticeable mild hissing wind noise, which feels like coming from center air vent, which I can nearly drown out with radio being on. It happens when A/C is on or off. I'm wondering what could be causing that noise? .

Was the windshield replaced? are all the parts on the front firmly attached and fit correctly? underside covers in place and secured correctly? I ask as once I had an oil change done in AZ and they put the second underside cove on over the first one instead of under it at the front lip, didn't notice until highway speed

Windshield wasn't impacted and seems everything in front is nice and tight. I've noticed space between front grill and hood is not 100% equal, slightly larger space on L side. Could that imperfection be the cause and thus air flow noise is transferred thru air vents?

These cars can be fairly quiet and powerful - Any small noise can take center stage.

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

Yes, I believe I remember on this forum a guy had a similar issue, he doubled up some duct tape and made a dam out of it for right behind the top of the grille insert and the whistling went away, turned out he was missing a trim strip from behind the grille, he just used the duct tape to find it, not repair it, did you check your underside panels for proper installation? also check your underhood rubber strips that the hood sits on when closed, mine come off their mounts on occasion, I armor-all them so they don't do that. Also you could check your airbox above the battery for good sealing and proper installation

Excellent points/hints, we'll do our due diligence!

There was a TSB on whistling noise at 60ish MPH caused by the grille, but not hissing. Its on facelift model. Attached.
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

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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......

Thanks, Prihadi, very helpful!

Where do you get the foam elements from? I didn't see a part number.

I have no idea, but foam is easy to buy from online stores.