so my buddy has a 91 a/t 5.0 mustang we seem to have a small leak but not sure what the part or line is called..the heater core is longer in use,it has been bypassed from the pevious owner stating that it was bad known issue on pony's.so i followed that line i noticed a small amount or collent in that area so i moved i decided to follow the throttle body hose and as i got to the bottom of it i noticed it was also wet.does anyone know what that is?is it a freeze plug.

 

if you can get some pictures that would help alot too

 

ill get some pics and post them after work...the leak is coming form this metal tube that sticks out of the lower intake manifold in the back right next to the last injector.that tube runs to the throttle body.