If your car suddenly has booming wind noise inside when you open the moonroof or sunroof the fix is easy and costs you nothing.
Moonroofs and sunroofs are growing in size and sophistication. With the New England winter season about to abruptly turn into the summer season, we’ve been using the panoramic moonroofs in our testers and love having the open air experience. Using the moonroofs reminded us that in some cases when we open the roof there is a booming wind noise inside the cabin. This is due to pressure changing rapidly as air flows over the top if the car and is disturbed a bit by uneven flow.
If you experience the booming sound when you open your moonroof there are three things you can do to make it go away. The first thing to check is that the built-in wind deflector pops up as it is supposed to when the glass or metal panel slides back. In one vehicle we drove this week, that failed to happen. A slight nudge from us, while we sat in the driver’s seat, was all it took for it to pop back up and then work normally. These roofs can sit for six or more months at a time. They may need a bit of a bump to wake up properly.
At some speeds, moonroofs make more noise and have more turbulent airflow than at others. In these situations, cracking the rear window on one side or both sides often completely changes the sound and wind flow to lower levels inside the cabin. If you like to have your driver’s window down when driving at moderate speeds you can also use this trick to keep the wind from coming into the vehicle. Give it a try.
One last trick is to not open the moonroof all the way. You will find that in most vehicles the moonroof will go back to a certain position about 80% of the way open and then stop. At this level of retraction, the airflow will usually be pretty calm at moderate speeds. If you then nudge the switch again, the roof will open to its 100% position. You will learn which amount works for that particular vehicle in various situations and speeds.
Try all these methods before you opt for any aftermarket add-on wind deflectors. Those are tacky and are not really necessary or helpful in almost every case.