89 2.1td 2 door, need help
 

hi, this is a 2.1td, 89, 2 door. I want to make it daily driver, i move air filter a find this. what is this( in green circle) and where this line go (must go or be connected), thx.https://cimg0.ibsrv.net/gimg/www.che...561c9712ed.jpg