Lude Generation

So that's an exotic one

Whenever I set the cabin fan to medium speed or more (AND ONLY WHEN ON THE COLD SETTING) I get a nasty whistling sound. At first I thought it was debris in the air channels or the blower, but then I found the culprit to be the outside intake !

It's located near the windshield wipers, below the hood, and the vortex of air between the hood and the black plastic cover mesh seems to create a nasty whistle so it's even noticeable inside the car. Here's a pic for better understanding.

https://i.imgur.com/MOxL5A7.jpg I think this is a Honda Accord, but its practically the same on our ludes.

The whistling is persistent while the hood is closed, but it stops when it's open - I presume it's because the choke point / bottleneck of the air is gone.

Anyone else had this problem? I tried googling a bit but no serious results came up

Yeah that's a weird one... Not heard of this problem on a lude before.
Have you checked all the cowl etc are properly fitted (all clips /seals in place)?

The fact that it only happens on cold would lead me to suggest something within the mixer unit is causing it tbh (possibly the mixer flap not fully closing hard up against the stops when in the cold position or the seal for it dislodged, causing a small gap for air to be sucked through at high speed?
The noise would probably be most noticeable to hear through the intake port because of largest are for sound to travel out from?

I know it's reviving an old thread, but I had the time to check it a bit more thoroughly today.
So the culprit was indeed the cowl / wiper motor cover. It has seals on its bottom side that press against the chassis and - more importantly - against the windshield.
These seals were gone on mine and therefore air was being sucked in between the windshield and this plastic cover. Here's a generic pic just to get a better idea of what was happening:

Air was being sucked in at the red line, creating a nasty vortex whistle.

Anyways, solved it by stuffing some generic window seal strip down there, the one you buy in long rolls at a convenience store