I am having an intermittent issue with my center vents opening and closing when set to “22”, but if I set the temp to 18 or lower, the center vents will always stay open, which led me to believe this was a soldering issue more than a pod issue. However, after pulling all the vacuum lines off the solenoid bank and testing them, they all hold vacuum perfectly except defrost 1 (red/white) which slooooooowly leaks down and then center flap, which doesn’t hold vacuum pressure at all. How could it be opening at all and be able to remain open if I set it colder if there’s absolutely no vacuum holding with a mityvac? I really don’t want to have to replace that thing after reading how difficult it is. Previous owner receipts say that all the pods were replaced 10k miles ago which was 2010. - Mike