Hello- '99 A6 (2.8 quattro) 188k- Recently on start up I get a squeal for 5-10 secs coming from front pass engine bay near air scoop (it is not the blower fan)- I have done searches on this topic most reveal a tranny issue- this is not the noise I am referring- When I turn off HVAC system it stops- The weather in the NE has been in the 40's- I am pointing to the electronic fan but want a way test or fix or replace?- Any tips or suggestions on what this could be?

This forum has been great- I have recently replaced Control Arms, Timing Belt, Tranny Fluid, Diff Fluids,- Car runs strong and my next fix after this issue will be my Struts (rookie mistake- I should have completed when replacing control arm- live and learn) and ABS Module are next- I plan to keep car until it leaves me on road- I have owned it 9 yrs with 29k (off lease)-

Tx to all and Happy Holidays!

 

i would think that it might be the serpentine belt?

 

The serpent belt was replaced last year. If I start car w/ havoc off all is good. When I start with hvac on the noise starts intermittently for just a few seconds. I won't hear it again until it has sat for a few hours. It is consistent at start up. The fan located on pass side, is that the aux fan? Anyway to test for squeak? Is it easy to disconnect and wire directly to battery to engage fan?

 

If you want to disable the fan...Just pull the fuse.

 

could be the ac compressor. it is on the passenger side. runs off the serp belt. and would account for the noise when the hvac is on. the econ button will turn it off

 

it was the aux fan. i replaced today and all is quiet again. tx for ur responses. just receive new struts and will replace this weekend!