Just took a look at another car a few hours ago.
2004, lower CCV lower oil drain hose was not rotted yet, however, very soft and on the way out, hose replaced.
DISA seal were in ok shape, could have used the O-ring, however, the DISA flap was spinning on shaft, pin probably broke, dropped out? New DISA ordered.
Original intake boots on the car, will be replacing them as a preventative measure as they are getting old and hard.
What I did find is whomever last worked on the car did not tighten up the upper intake hose to the MAF and the hose was about half way off the MAF.
So the basic problem was the upper intake boot was loose on the MAF and the car has a bad DISA.
This has been causing rough running when cold and codes to trigger. Simple problem, but the owner wants to keep the car at least 2+ more years and plans on keeping it reliable so the DISA, and intake boots will be replaced.