There seems to be a part on the air box on the side part no. 90910-12230 when I was working on changing out the dirty air filter I unplugged all the connections to make my job a little easier to remove the upper half out of my way.. Since i was curious I wanted to see if unplugging this part would change engine rpms or w.e but nothing had happened.. How can I tell if this part is malfunctioned or if its still working thanks

I see the part on the parts diagram . . . but I don't know what it is.
The description is "VALVE, DUTY VACUUM S"

What year is your ES? I don't have one of these.

The year of my car is a 2001

Show me a vacuum diagram and I'll figure it out.

Since I don't have photo bucket Ive provided you a link to the vacuum diagrams... here you will find the adequate info

http://www.lexussouthatlantaparts.co...=0&searchTerm=

I was unable to find that circuit in any of those diagrams. Can you take a picture of the diagram sticker under your hood? Also one from the top of the airbox including at least half of the Plenum (upper intake manifold)