2001 2.5i M54 Intake Vacuum Connection Question

[mpdewey]

Well.......Here is another question regarding vacuum connections!
I’m doing a complete coolant system changeout on my new-to-me “German Bobsled” that has 130K miles while it is in hibernation-mode. My little project involves changing out all the old hoses and piping, CCV set-up and dried-out vacuum lines.
After pulling the intake manifold to get to the coolant piping, I noticed that the 3 vacuum ports located closest to the firewall just don’t look right. The one-way valve hose is connected to a small port, while the other small port is capped and the large port is left untouched, as per the picture.

Most info I have seen while researching says the larger port should be capped, but no real info regarding the left-over smaller port. Even the RealOEM diagram shows the hose and 1 cap (assuming the large cap), but nothing about the 3rd port.

Anyone have any advice on this? There wasn’t any performance issues prior to parking it for the winter and I was very careful while taking it apart, so I didn’t rip anything off the ports. I planned on connecting everything back at to how it was, but just wanting some feedback from the knowledgeable folks with this forum.

BTW.......awesome information on lots of systems for these great cars - Thanks for all the assistance in keeping these cars running!

[rf900rkw]

The air injection one way valve goes to one port. The fuel pressure regulator goes to the F connector. Everything else on the manifold and CCV gets capped. And yes, the caps rot and fall off making for big vacuum leaks. Change them.

[mpdewey]

Will do......The hoses have been changed already and I had planned on swapping out the old caps (intake and CCV) as well.....I’ll cap off both intake ports and go from there.
Thanks for the info.