[It seems to me that changing air filter is not so easy in 2004 Scion Xa ?
][/b]

 

it wasnt so easy on my 06 either.(I assume it's the same) Everything is so close together and has several things attached to it. I didnt even take it all the way apart, I just opened it enough to take out the old one and wedge a new filter in there...

 

if you loosen the attached hose (prob will need phillips head screwdriver for this) it is easier to get the lid off