I was driving about 55 mph and twice within an hour, I heard an incredible vibration come from the rear driver's side ceiling. Then it sounded like it came from the driver's side dash. I held the ceiling the first time to see how bad it was. It felt awful. It vibrated through the moonroof. It only lasted maybe 45 seconds. Anyone else experience this? I have about 2800 miles on it. The temperature was between 16 and 20 degrees. The road was a paved highway, with just a dusting of snow on it, no ice.

Any thoughts?

 

Maybe buildup of ice/snow on a tire, making it out of balance? I doubt that it's hybrid related. Probably won't reoccur under warmer conditions.

 

Might one of the rear windows or the moonroof been open a crack? I've read about cars, vans, and SUVs of several kinds (hybrid and non-hybrid) that make an awful "vibration" noise when the rear windows are open.

 

Could it be related to the Moonroof and its track. When open, the moon roof slides backward (sound from the rear drivers side). Could the highway driving speed (55 mph) caused air to slip under the moonroof seal causing this noise?

 

Check the roof rack to see if the supporting legs, cross bars, or anything else is loose.

 

Acutally on the FEH this happens if you open the moonroof and DON'T crack the back windows.... Its pretty impressive at speed... sounds like you've got an Apache Attack helecopter hovering just over your roof.

Fortunatley just cracking the widows a touch gets rid of it.

 

Ah.... Harmonic resonance! Just like pipes in a pipe organ.

Did it sound like a contra bass A-flat, or A-sharp?
-John

 

My VW Golf had a heavy resonance thing with the moon-roof open all the way. They corrected the fault by putting an extra stop in the rotating switch at 80 open to prevent it. You could go past it with the windows open, but leave them colsed and go over 20mps and you'll get your ear drums popped!

It sounded like the original posted did not have the roof open, so it may not have been this...

Cheers,
rcomeau

 

I notice a lot of very low frequency rumbling with the windows in various positions. I can close all the windows. Or we have to tune the resonance out by adjusting windows or moon roof opening. I even have a clip that holds the back glass open a few inches.

This is probably NOT Alicia's problem, as it was too cold to have the windows open!

 

It hasn't vibrated since. But now I'm fully aware of the cool sound effects my moonroof is gonna do, once it gets above -4 degrees. BRRRR..... Tooo Cold.

It might have been a back window. I think my friend opened one of the windows, but not the moonroof. It might have been ice on a tire, but it didn't feel like it, it was really smooth. Checked the roofrack, good there. Don't know.

But I do know that my mpg has dropped to disgusting levels. Its sitting at 20.9 mpg today. Is that unheard of?

I also noticed that on the Menu it read that the car was on electric motor but then the rpm didn't drop down to EV. Is it suppose to? The helpful salesman at the Ford dealer told me it would. When this happened, you could not hear the gas engine, only the electric. Why wouldn't it drop down to EV in this state? Is it because its too cold out. (which it really is).

Thanks to all for puzzling it out for me.