[Cookman1005]

Hey guys,

We've had our 08 MDX for about a year and ever since buying it I've noticed this soft churning noise coming from behind the steering wheel. I've stuck my head under the steering wheel and can hear it a bit better, but I can't tell if it's coming from the steering column or maybe from left side of the center stack? The sound starts once the car is turned on and continuously goes until it's put in drive or reverse and the car starts moving.

Any ideas what this could be? I've had several mechanics thoroughly inspect the vehicle but none of them have noticed anything, although I keep forgetting to point it out.

 

[skirmich]

More than likely is the Air Mix Motor, It likes to go out on many older Honda & Acura products.
The Air Mix Motor is located at your knee level height behind the lower plastic steering trim panel in the covered part of the dashboard you will have to remove the lower cover that holds the ambient LED and you will see it attached to the center console stack behind the Radio. There are 2 of them, 1 for the driver and 1 for the passenger (Dual Zone Climate) and they are attached on each side with 4 screws.

 

[-jon-]

More than likely is the Air Mix Motor, It likes to go out on many older Honda & Acura products.
The Air Mix Motor is located at your knee level height behind the lower plastic steering trim panel in the covered part of the dashboard you will have to remove the lower cover that holds the ambient LED and you will see it attached to the center console stack behind the Radio. There are 2 of them, 1 for the driver and 1 for the passenger (Dual Zone Climate) and they are attached on each side with 4 screws.

This was my thought, too. Ours has been clattering for quite some time so last weekend I took it out, cleaned it and lubed it. Seems to be working much better now. The thing is a PIA to get to … you have to contort your body and move stuff out of the way. Unmounting the control box that's next to it makes the job a whole lot easier (the bracket is held on by a bolt near the brake pedal). I chose to clean the module vs paying $200-$300 for a replacement part.

You might find that a symptom of the mix motor not working properly is that the driver's side doesn't cool well or it blows hot air when you expect cool air.

 

[Cookman1005]

Thanks guys, I appreciate the responses. I'll definitely look into the air mix motor. However, is it normal for that to stop making noise once you start moving? I would think anything related to the cooling system would run the same regardless of if you're in park or are driving.

 

[skirmich]

The mix motor in the MDX likes to cycle even before you start the engine (Key on Position I) I believe it does this because the MDX keeps your cabin temperature even with the A/C Off so it has to move the mix motor in order to regain the temperature set after turning the A/C Off. The only way it wont move is if you set either of the max settings be Max Cold or Max Hot because the A/C does not regulate the temperature on any of those max settings.