cranks good. Rough idle. Throttle let off it stalls. Help?

Had simular simptons and it was the MAP sensor on my 2001 Mercury Sable. Less than a 100 to have it fix by mechanic. If you have the ability it is realively easy fix.

Ok idk if this car has the vacuum port between the valve cover and the firewall but my 98 did the same exact thing even caught on fire at one point because it back fired lol anyway I plugged this vacuum hose back up now it runs fine again