First off let me come right out and say I am not a car guy, but I do know what some parts of the care a called . I'm just trying to fix a seemingly easy issue and need a little assistance. I've looked through the forum and it appears I have a problem with the hvac vacuum lines. This is my story please let me know if you can help.

1. 2 days ago the air was blowing out the main front vents and all of the sudden switched to blowing out the defrost and floor vents.
2. Temperature controls work properly.
3. I found lots of information on this forum (you guys rock) on what the cause of this problem is.
4. I'm new at this but I think I may have found the issue just need help on what to do next.

Photo 1
I found the vacuum reservoir, I disconnected a black hose and it had good vacuum pressure. I did not hear the reservoir leaking.


Photo 2
I found where the tubes pass through the firewall. No breaks or leakage here.


Photo3
I followed the black tube and it went behind the motor and came to this spot near the alternator. At this point it had been connected to a red hose. I pulled the red hose of this connector and there was good vacuum pressure.


Photo 4
I then followed the grey line to this spot under the air intake tube thing. I pulled this off the connector and there was no vacuum pressure.


I then followed the grey line and it disappears behind the center console. I think this grey line is the problem, however not sure how to identify where the leak is or were the grey line is going.

Am I doing this right and where do I go from here?

Thanks,
Jared