Hose disconnected, can't find where it goes?

I recently replaced the heater core in my daughter's ford escort 2001.  It has the
2.0 SOHC engine.  I accidently disconnected two hoses that goe across the
location of the heater core hoses near the firewall.  They were both off of two
chrome tubes that turn into rubber hoses about the size of your pinky finger.  
one of them went to a plastic fitting bolted above the heater core at the top of
the back of the engine compartment.  I could not for the life of me figure out
where the other came from so I left unhooked (I know stupid).  The "Check
Engine" light is now on and it seems to be idling very rough.  I can't find a
diagram that shows what these are and where they go?  I am not sure if I
attached the right one to the plastic piece??? Any thoughts?  Thank you in
advance!