Replaced your oil/air separator? Watch out for this.
 

I'm still trying to track down my P1502 problem so last week I pulled out the intake to check things out. When I pulled on one of the vacuum lines, it snapped in half like a pretzel. I felt the other ones, and they were hard as a rock. I pulled the broken vacuum hose off and there was oil inside it which I believe is from the bad oil/air separator. The oil must have deteriorated/hardened the vacuum lines and made them very brittle. I decided to replace the vacuum lines while I had everything out and they were all brittle and broke easily.

Just something you might want to watch for if your oil/air separator was letting oil into the intake at some time. :cheers: