Im greedy!!!! Haha. I have the stock vx and a vx swapped sedan. I've had 2 other vxs that I stripped of all the vx specific parts. I have a ton of parts for them.
I really can't believe I'm putting this much effort into a pcv valve system. Kind of ironic out of all the vx specific systems this is the one that gives the most problems.
Anyhow I looked at my 4 z1 engines and 2 d15b7 engines. Low and behold one of my Z1s had the elusive empty valve up top. That in itself totally disproves the majestic diagram. It cannot be looked at as a general 5th gen civic diagram. Who knows how many times it has been revised. In the picture below you will see I have 4 items. The elbow and the blue valve are from the same engine. The brown one is from another z1 and finally we have the b7 on the end.
Both b7s have the empty valve at the bottom and the real pcv at the top. In this case it does follow the majestic diagram. HOWEVER ALL 4 z1 breather valves are NOT empty they all have guts. This also contradicts the majestic diagram. They all have the same p07 part number as tom0 said. Here are some more pics.
In conclusion, if someone were investigating their pcv system to find out where it is look at the breather FIRST!! If the connector looks anything like the blue or brown ones then you are ok to gut the upper one.(if someone has installed a valve, if it's the original open connector leave it alone) If it looks more like my b7 one then make sure the upper elbow has the guts in it. All systems have a pcv valve.
In escense both of us are right and both are wrong. My initial statement about there being no valve on a z1 is wrong and I stand corrected by my findings. And if nobody believes it hey no skin off my back. In the end the worst thing that could happen is someone runs 2 valves and how much will that really affect economy? Probably zilch.
Ok I'm done blabbing.
Edit: oh another thing to note. Both the empty valves on the b7s and the empty elbow at the top of the vx were void of part numbers.