Oil filler neck...where connects to the down-facing nipple?
 

On the oil filler neck there are two nipples - one faces left, one faces down. I know the one facing left connects to the UIM.

Where does the down-facing nipple connect? I am non-seq now, so maybe I don't use it and it needs to be capped?

I just spent 10 minutes scanning the '93 service manual. They tell you to connect the left-facing nipple to the UIM, but they never mention what connects to the down-facing one.

Pic:
https://www.rx7club.com/attachment.p...1&d=1195490013

thanks

Downward one connects to the primary turbo inlet (constant vacuum source). I'd remove the one running to the UIM with the PCV valve. As long as you have the other vent line to the turbo, the PCV is just another potential boost leak. After 93 the line with the PCV valve was no longer installed at the factory.

Agreed. 100%

mines a 94 and it has the pcv to the manifold.

that vent line nipple should be straight down from the oil fill neck. its a hard line that bolts onto the front plate with a banjo bolt and the turbo oil feed line.
kinda tough to c. but its there