Rx350 Thermostat Help

[kyancy]

Hi all. My Wife's 2008 RX350 started chattering at startup recently, and then the other day her heater wouldnt get hot and eventually her vehicle stalled. After sitting in the cold for about 30 minutes, I was able to get there and it started up and I limped her home.

Thought I would start by replacing the thermostat thinking it might be stuck open. I've done several of these on othe models, but it's not as obivious where to go on her RX350. There is no top heater house that goes directly to an obvious thermostat housing. It appears that it may be on left side of the engine (to my right when facing from front of car), but that house appears to go into some sort of dual housing and has additional smaller houses connected. I'm hesitant to try to disconnect all this if I'm looking in the wrong place.

Any guidance on location and replacement of the thermostat is very much appreciated. I would expect replacing a $20 thermostat and gaskets should be a simple task, but maybe the lexus models make it so difficult you have to take to dealer? Thank you again!

[ColinBarber]

does this help:

http://parts.jmlexus.com/catalog-4/diagram/lexus/2007/rx350/cooling-system/cooling/hoses-and-lines/8913057

I would think there is something more serious than just a stuck thermostat for the engine to stall.