jedblack

I noticed the other day when I turn on the heat, it seem to put little load on the engine(almost as if the AC was running when the compressor engages). When this happens it seem to produce and audible(in the cabin) whining/whirling/occulting noise that increases/decreases with engine RPM.

The noise completely disappears when I push "off" on the climate control pad

Could this possibly be the blower motor or blower motor resistor?

4Driver4

Blower motor.

jedblack

Thanks 4driver4....

hewtown

Pretty much my symptoms as well, however, the whining sound doesn't happen immediately or consistently. It only happens after the heat has been running for awhile. Does this sound like the blower motor as well? Any tips on the DIY job and the overall difficulty?

Also, my heat only works when I'm accelerating (and even then it seems to be lackluster heat strength).... I've read this could be due to gunk in the heater core, and can be remedied with a heater core flush. Any possibility of this symptom being related to the blower motor as opposed to the heater core??

ALSO, I have a slow leak in my coolant system, presumably the auxiliary water pump (common for my 2001 2.7T). However, I don't have the experience to properly diagnose this with any level of confidence. So my question is, any chance this leak is related to either of the two problems described above?

ALSO again, I have had those little black foam pieces pop out of my defrost vents lately... what the heck is that stuff and is it related?

Yeah... lots of fun with my HVAC and coolant systems lately. Thanks in advance, and sorry if any of my questions are silly/obvious to the experts.

jedblack

@hewtown,

Its seems like it would be pretty easy to swap the blower motor. You need to pull the glove box..

Audi > C5 > 1998-2005
Body Interior
68 - Storage compartments, covers and trim parts
Glove box, removing and installing1 - Glove box
Removing

Open glove box lid and remove bolts - 3 - (3x).
Remove bolts - 4 - (2x).
Remove glove box downward.
Disconnect connector - 2 - .
Installing
Position strip - 5 - with rubber studs - 6 - against instrument panel - 7 - from underneath and install glove box.
2 - Connector
3 - Bolts (3x)
Tightening torque 5 Nm
4 - Bolts (2x)
Tightening torque 5 Nm
5 - Strip
6 - Rubber studs
7 - Instrument panel

Donuts

If you need a replacement blower motor let me know as I have an extra one. -- Joe

Teutonix

If the noise varies with engine RPM, I wouldn't be looking at the blower motor. Does it also disappear if you hit the ECON button? I just had to swap out an A/C compressor on my wife's 3.0 because the bearings took a **** and started squealing anytime the A/C clutch was engaged.

Oh... and yes, the A/C compressor can run any time of year, not just in summer.

jedblack

did you mean you had to swap out the AC compressor -vs- AC condenser?

Either case i find it interesting... I havent tried it with ECON mode on.

Teutonix

Yes- Fixed the typo.

RMsALFA

Before you start tearing the glovebox off, remove the cabin air filter and make sure you don't have "stuff" wedged down underneath it.

I have had funny noises like that twice. Once it WAS the blower which was replaced when the car still had it's factory warranty (the tech told me how to do it and it didn't sound too hard) and once it was crud that somehow got through the filter and wedged in the blower intake.