CeoStatus0

So I'm driving the IS to work and I turn the AC on Auto set at 75 and it pushes out at 3 bars... I have my Ipod pluged in and just listening to music... about 25 mins into it i'm slowing down to a traffic light and a track on the Ipod just ended (so the car is silent) and i hear a fluttering sound comming form the front pass side... I thought it was the connection from my Ipod jack so i turn the volume down and it went away..

music is off and i drive to the next light and as i hit the brake it i faintly here the fluttering sound again and it gets louder as i come to a complete stop. So its not beacuse of my Ipod its because of the AC... then i hit the button to drop the AC output down to 2 bars and the sound goes away.. but when i hit it up to 3 bars the fluttering sound comes up.

I left it back on 2 bars until I got to work, parked and left there all day... now as i drive home from work i test it out again.. i turn the ac on pass 3 bars.. and the fluttering didn't come up...But i drive the IS once or twice a week so i'm a little concerned... I'm going to take the car out tomorrow and see if it comes up again.. but just wondering if anyone knows of this

I'm taking the car back to dealer this week for a 3rd tinting job... i'm gonna ask them about it then

jezza

People have this weird idea that the AC actually operates at different levels... it doesn't. In terms of work done by the compressor, it's either ON or OFF. The climate control varies the temperature by mixing cold air off the compressor with heated air off the engine.

As for the noise, if it's only audible at a certain fan setting, it's probably the fan. Just take it in if you're worried.

Bichon

It's not a wierd idea, and yes it does.

Simply not true. The IS has a variable displacement compressor that varies the capacity of the compressor based on both cooling/defrosting load and torque availablility as calculated by the engine management computer.

(Haven't you noticed that when you romp on the gas on a hot day, the car neither accelerates like a dog, nor gives you a face full of warm air, as cars without a variable displacement compressor do?)

Read about it here: http://www.globaldensoproducts.com/c...ompressor.html

It does that too, mainly to provide defrosting and humidity control.

On this point we agree. Could be something as simple as a bit of foreign matter (e.g. a leaf) making contact with the blower at higher fan speeds.

CeoStatus0

I took the car out today and the sound is gone... the fluttering was there as soon as i took it out of the garage... at 3 bars it was there then i was playing around with it.. 4 bars back to 3 bars, 5 bars back to 3 bars.. and the sound is gone...

yea i bet was something stuck by fan/blower

i'm gonna take it out the couple days before i bring back to the dealer to see if the problem is completely gone

lobuxracer

iTrader: (2)

Thanks for the link Bichon! I didn't know about this and would have made the same mistake if I hadn't seen that. Now I understand why I didn't see a significant difference in fuel economy on a mildly warm day and I saw quite a bit on a really hot day.