Odd Sound from under passenger dash?

[sylcurt]

Not a huge concern here, but more curiosity...

When I start the car cold (first start of day, or after sitting a while) I am noticing a sound from under the passenger footwell area that I never noticed previously.

Tough to describe, but here goes...its like a fan motor is running in the background on low speed very faintly,
(but it is still there if I turn off my HVAC system completely)..the fan has a different sound when running, you can disticntly tell the difference, it just sounds like it.

If anyone had a Chev pickup from like 25 yrs ago, and you could never shut the HVAC fan off totally, was always running in the background on very low speed, its like than kind of sound.(the motor sound, not the air moving)

or like when you have your stereo on, and there is a bit of alternator noise faintly in the background.
(I know it isn't alternator noise, I am just comparing it to that...)
And if the stereo is off, it is still there. Does not get louder or change pitch with higher RPM's.

It seems to go away as car warms up, and it is there when idling/warming up....

Only thing I have done in this area is removed factory subwoofer box, in lieu of the Angus Sub box...and relocate the module that was there to up under the glove box...(power steering module I think)

Could it be ambient noise from my power steering module?
I thought that was straight electrical?...is there something else in that area that could cause this sound?

Everything is running perfect so no concerns per say, and once you are driving , even with stereo off, you don't hear it (it either goes away as car warms up, or drowned out by engine...)

Thoughts or suggestions?

Thanks,
Curtis

 

[BTL3.0]

I notice the HVAC smal fan next to the cig. plug will run even if the HVAC is turn off. Could it be that is what you are hearing? Try this, turn key to ON position with out starting. Can you hear it? If yes, try turn key down to ACC. Can you hear it? If no then its the small fan. If yes then I have no clue. The small fan suck in air so when yo use yur HVAC it can auto adjust to the temp.

 

[nsxtasy]

That's correct. It's probably the aspirator fan that is located behind the small vents on the bottom of the vertical part of the center console. Over time, it accumulates dust/dirt and can get noisy, as described in the Wiki here.

In 21 years of NSX ownership, I've tried three different solutions: (1) sprayed a can of compressed air through the vents, didn't fix the problem; (2) replaced the aspirator fan - fixed the problem, but it cost several hundred dollars; and (3) Briank cleaned/refurbished the fan - fixed the problem, was particularly convenient for me because I was there with my car in person, but I'm sure he could do the same if you're willing to take it out of your car and ship it to him.

 

[ThumperAC]

I could also be from the sounds system, the amp in particular.

 

[Briank]

I do have one aspirator fan I do exchanges with so you only have to take the console apart once. $35 + $100 core deposit.

 

[docjohn]

If it is your aspirator fan then take Brian up on his offer,as per Larry B I got the last new replacement in the US 5 mo ago.Not sure if they have sent any more to the US.

 

[stevieray122854]

I do have one aspirator fan I do exchanges with so you only have to take the console apart once. $35 + $100 core deposit.

+ 1000000. Brian is the best. I just did the aspirator fan swap with him and it took all of 4 days from beginning to end. He's also really great at troubleshooting other various and sundry Honda electrical parts (e.g., Prelude main relay & Compressor Control Unit), too. Hit him up---

 

[nsxtasy]

I could also be from the sounds system, the amp in particular.

Highly unlikely. When the amps in the sound system go, they typically make loud "scratchy" type sounds - very different from this description above:

its like a fan motor is running in the background on low speed very faintly,
(but it is still there if I turn off my HVAC system completely)

That's a perfect description of the noise coming from a dirty aspirator fan.

 

[sylcurt]

Yes, after giving it another listen, I beleive it is the aspirator fan...seems to be exactly where the little notched holes in the console are.

I hadn't planned on taking my console apart again this winter (did it last year for the stereo upgrade and wiring) but will do so I guess.

Other than the annoying sound, what is the repercussions of not getting it fixed? (Just throwing off the auto climate control?)

 

[Vega$ NSX]

Before I throw in my thoughts as to the cause, let me ask you this first. Do you believe that leprechauns can get hot?

 

[Briank]

Yes, after giving it another listen, I beleive it is the aspirator fan...seems to be exactly where the little notched holes in the console are.

I hadn't planned on taking my console apart again this winter (did it last year for the stereo upgrade and wiring) but will do so I guess.

Other than the annoying sound, what is the repercussions of not getting it fixed? (Just throwing off the auto climate control?)

Its just noise caused by loose bearing on the little fan that pulls air across the sensor. It does not need to be fixed unless it annoys you.

 

[BTL3.0]

Just unplug it if it bother u that much.

 

[Briank]

I would not unplug is since that will disconnect the temp. sensor and the ccu will not work correctly.

 

[BTL3.0]

I would not unplug is since that will disconnect the temp. sensor and the ccu will not work correctly.

so what kind of probkem woukd happen if we unplug them?? Reason I ask, people have the sos gauges plate. When doing that, u would need to unplug the fan.. Unlesd u mod it to make it attach some how. I have a custom gauge plate but I mod it so the fan is still funtional.