Is it the one with the hose attached or the one just to the left of it?
Hose is pcv. This must be hooked up or you are possibly building pressure in the crankcase...which..btw would cause it to fall on it's face. PCV gets routed between map and throttle plate.
If you have an L67 TB and want to make the pcv functional, follow the first 4-5 pics in the first post of this thread to drill and tap your L67 TB. Then run the hose from that pcv nipple to the new nipple you put in your TB. If you need more pics..holler. I have this on my car.
Other one is the L32 evap hole and needs to be plugged and or have the evap routed into it. It's easy to tap with a 1/4" npt and put a nipple in it to put the vacuum hose to it. I know..cause I did it last night.
