rough idle and engine stalls

check your pcv tube for vacuum leaks.

I have a 2004 explorer sport track my unit was running rough and would not start after replacing a few parts Iwas under under crank pulley and noticed the pully didn't look right the pully seperated and th belt was sitting on the broken part of the crank. I replaced the crankshaft position sensor also as the old one was destroyed. also auto zone shows some good diagrams for repair work.hope this helps