M104 vacuum lines

Hi, I have a ‘93 300E m104 2.8 . Can someone please tell me about the vacuum ports near the throttle body? I have 2 lines running to a valve (001 140 176U) which is connected to the left port (if facing motor) and the right port is capped. I’d let it remain like that but I saw one in the junkyard that had a tube connected to the right port. Is mine correct? Junkyard correct? Both correct?
Thank You.