Looks like leaking gaskets unfortunately as this seems endemic with this engine. Spray on the edge of the upper intake manifold gasket. The RH side when standing infront of the car is easiest to see and to spray on to make sure.
The job is not hard - just tedious - especially the cleaning of the manifold. Lots of info on this site about it. Just be careful and use gloves if you use a Xylene based solvent as it is bad stuff. I got some Felpro gaskets PArt #MS 95726 which seem better than the Ford OEM gaskets at half the price....
Suggest that once you have the upper manifold off that you also do the lowwer one as the gaskets are the same construction. Clean the butterfly valve and the throttle body as well when you have everything apart and make sure you clean the EGR passeges on the UIM.
With everything off it is a good idea to do the plug wires and plugs as well as the PCV valve as they will be very accessable instead of a PITA... I also replaced the EGR valve when I had everything off as the large nut from the exhaust pipe is almost impossible to get off without the UIM off and this part seems to also cause trouble according to experiences from foks here.
Good luck.
Cheers, William
