W124.128 shutoff issue

[Capn Jonas]

My car is a 1990 2.5 diesel which recently stopped shutting off when the ignition key was shut off. Per conversations on this site, I attached a mityvac to the shutoff activator and the engine shut off immediately.

The vacuum line coming from the actuator is 4mm brown w/blue which goes into the dash area and turns toward the center, behind A/C equipment. This line has no vacuum when the key is shut off, as measured at the actuator.
This line, per my manual, should go to the ignition key but if it does so it is indirect.
The lines attached to the key are black w/grn and black and are quite a bit larger and tight. Although I have removed the cover under the instrument panel (68-150) I can't visually see where this stuff is going as of now. Would appreciate your thoughts.