I have a 1997 Expedition with 219,000 miles on it. I am currently having a fast idle problem that I can not resolve. The vehicle idles at about 800k on cold start but if you touch the pedal even slightly it will idle up and fluctuate between 1300 and 1500 and idles at about 1100 while in gear. If you hit the gas and release it the idle only returns to about 1600 and will gradually climb to about 1900 over the next minute. Idle is always high on warm starts and after driving. No problems with stalls or cutouts. I originally had a code of P0320 which led to testing and changed the original IAC valve as it was showing low resistance readings (approximately 4k ohms). The problem still persists. I performed voltage readings of the IAC’s connector with the ignition switch in the “ON” position as well as resistance of the new IAC which all checked good. The MIL light is not on and there are not codes in memory. What would be my next logical step in rectifying this problem?
I thank you in advance for you time and consideration.
Tuesday, February 14th, 2006 AT 2:21 PM