There's a weird noise, sort of a ratatat (like a quite machine gun?) from my dashboard. No clue why. It stops after a few moments (30 -60 seconds). After that, everything about the car seems fine. But this noise is _wrong_ and natch, I'm concerned.

Scares me because I've never heard of this and cannot find anything similar on Acurazine.

Any ideas?

I have recorded it several times and Acurazine won't accept recordings longer than 5M and my shortest is 13. I'm on my way to work soon, and will try to get a short recording, haha. and will post it when I'm back from teaching

 

There is a fairly common problem in RDXs of a HVAC blend door actuator making sort of groaning noise while it adjusts. It sounds like it is coming from under the steering wheel.
On my wife's 08 MDX, the CD changer does not & has not worked. Now it makes a horrible loud ratatat sound for a bit when you first start the vehicle. But you can pretty clearly tell it is coming from the CD changer area.

 

Really!? That's great info and it does sound like mine.
Let me see if I can upload the sound here
Ah, it worked. Is this a similar sound?(oops, forgive my dust and cat fur on the dash)
When I leave to teach soon (I teach afternoon and evening) I'll check the CD. The radio is fine.
Are you planning on getting it fixed? Should I take it to the autoshop?

Thanks for your input!!

 

I can confirm the passenger blend door is your cause. I just replaced mine about 3 days ago due to the same sound. You can pick them up online for like $50 and it takes some patience to replace but can be done in about 20 minutes. It requires a T15 torx bit though.

 

 

It's definitely a tighter fit, I had scratched up hands for a few days. You don't need to take the blower motor out.

The climate control box will be 2 electrical connectors and 3 torx screws. after that's out of the way, it's 3 torx screws for the blend door actuator. Make sure when you go back on that you get the pieces lined up, they're basically dowel pins that fit in a curved plastic bit. Otherwise, it's rather straight forward. I personally have a 1/4 inch T15 torx that allowed me to do the job quickly, and if I remember, I may have used a small 3 inch extension on one or two of the screws, but nothing more than those tools are needed (I guess aside from the 2 10mm bolts to pull the glove box off)

 

 

I completely got mixed up with another car/part, you don't need the torx, just a 7mm socket to get the climate control box and blend door motor off. My apologies there.

a 10mm to get the glovebox off, and a 1/4 inch 7mm socket/ratchet for the rest. And you are correct, passenger blend door motor. the mode motor is actually worse to get to so pray you don't ever have to do that one!

 

 

Replaced it today. No need to remove the blower, but it was really tight and you need to have short screw-driver 2-3in, there is very little room to remove the screws. Works great, part cost under $50, and dealer wanted $320! took about an hour.

 

Awesome! Super nice to be able to start your car and not have 60 seconds of ear piercing rattle isn't it?

 

 

Thanks for all your suggestions folks. I'm very unmechanical, so I copied your suggestions to take to my mechanic and planned to post my results.
Time went on.
I got accustomed to the noise. It would go on for a few minutes then stop.
I don't have a clue when the noise stopped altogether.
So, I guess I have the first self-healing car.
Thanks for the input and reassurance that it wasn't a sign of the car's dying.
It didn't
Best regards,
PB

 

Either a self-healing car, or the mix motor just died altogether after all its struggles...