2000 GT idling problem

[bevgt108]

I recently pressure washed my wifes engine.That's how the problem started! The engine started missing. Fearing water had gotten down to the spark pluge holes  I took out all the coil over hardware and plugs drying them and all the sparkplug holes.The car ran very well but the idle was very high 1100rpm. The rpms would stay high through all gears not falling as it should between shifts. If you took your foot off the gas pedal the engine would keep the car rolling down the road. When you pushed in the clutch the rpm would settle at 1500rpm and stay there untill you came to a complete stop. Then it will return to 1100rpm. The engine finaly set a code P1506 which is a defective idle controll valve. I replaced it with one from Advance Auto and cleared the codes from the computer. It is still idling high and now the rpm is fluctuating at times while driving. What gives? Am I missing somthing ? Could this be the throttle sensor? The car has not set any more codes yet. Please help before my sweet wife condems me to pergatory for messing up her toy

[bevgt108]

This topic has been read a 136 times and no responce ? I guess I am on my own!

[Soaring]

I have to admit that I know very little about the computer controlled cars.  If it was mine, I'd take it to the Ford house and have them plug in their fancy computer to determine what is wrong.  If it was an old Mustang, I would think about checking all the vacuum hoses.  Sounds like a vacuum leak.  But, the Sn95 doesn't have vacuum hoses does it?

[rmodel65]

idk how great the iac from the zone is? you did use a new gasket didnt you? personally i would have cleaned the stock one out with brake cleaner then reinstalled it 1st.  i would try cleaning the old iac reinstall it. i also would disconnect the battery for about 15 min then restart the car

[bevgt108]

I recently took off the new IAC motor and cleaned and reininstalled the old IAC motor. The idles has come down some but it is not what it should be. The engine still idles high untill you come to a complete stop. Then it drops to around 1100rpm. I took vise grip pliars and turned the idle screw on the throttle body and adjusted the RPM,s down to around 900rpm. I have also disconnected the battery for an hour or so to help reset the computer. Also I bought a scan tool after the check engine light came on again to get the codes. The codes were p1506 and p1504. I will look at the CD disk that came with the scan tool to determine what the mean.