Haven't had much time to mess with the van, just wanted to update progress. Replaced the cloth covered lines that run from the intake-- solenoid. One of the lines slipped off easily so I was hoping that was the leak source. But, alas, it was not to be. Took a drive, no codes. After the next drive a few days later checked for codes, P1582 showing but no CEL. Next day CEL back on. At least the P0411 code isn't coming up.
The Mityvac arrived today (the mailman launched it from about 12' to the porch, which pissed me off) so when I get a chance, going to test the line from the solenoid to the Combi. I know that line should be changed, regardless, but for now my quest is just to get it through inspection. I also realize that I should be checking other things, but I want to pinpoint the exact cause of what causing this P1582 code. I've scoured the net and found so many different fixes, such as replacing TV's and 's.