Im taking a look at i may buy today, and i noticed something in the engine pic. Can someone tell me whats suppose to go where i circled in red.

BTW: its an 1988 Iroc, 350ci

Thanks

 

IIRC, that's just a valve to release the pressure in the A/C system. Kind of like the valve stems on your tires.
So, to answer your question, I believe it is as it should be.

 

There is normaly a black cap covering that. A A/C tech would connect his gauges there and there in another smaller one down the line to check and refill your A/C system

 

I believe the above 2 posters are correct, that is a standard schreader valve that you can use to purge or pressure test the system. If you buy an "AC recharge kit" from your local parts store it'll most likely connect to this port.

-Zander

 

Yes, that is the low pressure side where you fill up the A/C system with refridgerant. Ive had to do this a time or two. The other one on the hose is the high side, you do not want to use this to fill up the system as this has high pressure when A/C compressor is running.