ISport350

Hey good morning CL!
I have been on and off the site for the past several months and really appreciate this great resource everyone has built. I didn't know I would need help so soon as I just purchased a 2007 IS350 over the weekend. This is our second Lexus as we bought an RX330 in the fall for my wife. I digress....

I need your expert help! When I start the car there is a loud noise that kicks on for about 10-20 seconds that sounds like a compressor. It will kick on whether or not the AC is running or completely off. I have been unable to reproduce it by command. It usually occurs at start up and then yesterday it kicked on 4 separate times in the course of a 20 minute drive. The noise is loudest when I open the glove compartment so it seems to indicate it is coming from that side of the engine bay. Nothing looks out of place and I am stumped. The AC runs ice cold and the compressor for that runs separately. I will try to record the sound sometime today.

Any ideas? Thank everyone!

Bichon

Are you sure it is coming from the engine bay? My first thought is that someone broke the air mix servo on the HVAC system by trying to replace the cabin filter without setting recirc mode first.

ISport350

Thanks for the suggestion. Where is the "air mix servo"?

More info:
Drove the car Saturday, Sunday, Monday...and the described sound did not occur until Monday night when I pulled into the garage and turned the car off. Having left the window down i pressed the start button (with brake down) and tried rolling up the window...failing to realize that to run the accessories all i needed to do was press the start button without the brake. I went ahead and started the car, rolled up the window and that's the moment the sound started. The only thing that changed was on Sunday I put a new battery in.

The sounds occurs whether the HVAC is running on full blast or is turned off. The AC blows cold.

Bichon

Air mix servo is behind the glovebox, but in the cabin. Broken air mix servo would be heard even if you had the A/C compressor off, but shouldn't be heard if you had the whole HVAC system turned off. A recording of the sound would definitely be helpful.

edit: found this video on YouTube showing what a broken servo sounds like:

ISport350

That's the exact noise right there.

Next question... is there a way to remedy the situation or should I plan on finding and replacing the part (suggestions here?)

Bichon

There is a DIY on the forum with instructions on fixing it, which I'll link below. It's an expensive repair at the dealer.

https://www.clublexus.com/forums/is-...g-to-circ.html

Gville350

iTrader: (10)

Bummer! Not an easy or fun repair.

Return to the place where you purchased it and pray they cover the fix.

But welcome and enjoy the IS350!