[gyee57]

I have a 2004 Sienna, where is the Intake air temperature sensor located?
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[toyomoho]

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

 

[SiennaSC98]

I have a 2004 Sienna, where is the Intake air temperature sensor located?
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I think it is built-in, inside the MAF (Mass Air Flow) meter.