Installed New Motor running rough. Help!
 

I purchased a 2007 Fusion with 36k miles on it. Long story short. 1000 miles later the motor went out.... Ford wouldn't warranty it.... So I was stuck replacing the motor myself to save the 3k labor bill ford wanted. So I'm finished swapping motors. I don't think I missed any sensors but I don't have the exhaust hooked back up. The engine starts fine but idles very rough and the throttle is non responsive. Is it in a safe mode of some sort? I have the exaust manifold on but thats it. Does the rest need installed for back pressure or something? Any help would be appreciated!