For months I've been hearing the sound of rushing air coming from the direction of the front passenger side door. I've been trying to ignore it, but it's been getting worse. Today I noticed what appears to be a narrow gap between the rubber stripping and the front windshield near the wiper blade tip. Could that be where air is leaking in?
Have someone blow at the spot with a compressed air gun (100PSI, a few inches away to avoid damaging gaskets), with you sitting in the car, and all the windows and doors closed. You should be able to hear if air is leaking in, from that spot. Personally, I would be more concerned with rain water leaking in. Most of the ECUs are located under the dash on the passenger side.
Do the dollar bill test. Close the door on a dollar bill and pull it out to see how tight the seal is all the way around.
Just a suggestion. Have you had your windshield replaced? If you purchased the car used than it may have been changed and there may be a airleak from the windshield. Easiest way to check to see if it has been replaced is to see what brand windshield is in there. If it has a "Toyota" logo than it is the OEM one. If not than it's been replaced and you may have an air leak.
It was actually a gap between the stripping and the molding. The body shop didn't think it was a big deal, but fixed it anyways for free since it was near where they had done some body work. I doubt that was the source of the sound I was hearing, even though the sound now seems somewhat muted. I just think I've just been hypersensitive ever since I got into a minor front end collision. I now notice every little thing and magnify it manyfold.