Can someone please tell me what this is and what it's function is?!?! I think it has something to do with my vacuum advance. Do i need it? Is it installed correctly? Thank you in advance.

 

It's a TCS (Transmission Controlled Spark) solenoid. It blocks or opens the vacuum to the distributor under certain temps or if the trans is in certain gears. The short story is it's smog stuff and you don't really need it. Where the black plug is should be open to air, no plug and no vacuum line, just open. Some cars had a small foam filter there. It's hard to see how it's hooked up, the pictures are too fuzzy.