I will try to add some freon first. The idle surging happens when the shift lever is in P or N position, even after a long ride. If the shift is in D position, everything looks fine even when the car is in full stop. I looked through the archive and found on Zetec poor idle when A/C is on may be caused by the failure of the Air Conditioning Pressure Control Switch. Does this apply to my Duratec?
