The link below should provide access to a service manual. Usually the sensor attaches to the air cleaner box somewhere on the side.
http://d01.megashares.com/?d01=a8372a3
http://d01.megashares.com/?d01=a8372a3
I think it is built-in, inside the MAF (Mass Air Flow) meter.gyee57 said:I have a 2004 Sienna, where is the Intake air temperature sensor located?