I suspect you are talking about the check valve with 1/8 in port in the side for ignition vacuum built into the main vacuum hose to booster. I dont remember what I was doing but I broke that port off also at one time I had to replace the whole hose assembly. The car was my daily driver at the time so I just went to local parts store and bought a signifigantly long section of 1/8" vacuum hose and a tee and stole vacuum from in front of the valve cover where the tree of vacuum lines collect for the egr components allowing the key to turn off engine. Then nicely zip tied it along other lines back to brown plastic tube for ignition switch by fender. I used electrical tape wrapped tightly and many times around broken port on main hose to prevent vacuum leak. (THIS WAS A TEMPORARY REPAIR) till the new hose shipped in . It worked flawlessly and I just hooked everthing back correct with new main hose when it came. So I think the answer to your question is no you cannot replace just that part I seem to remember it being a shrink or special fit no way it was going to be able to be R&R. Maybe someone will chime in otherwise. Hope this helps

Arlo

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