f 150 rough idle

My '97 f 150 has an intermittant rough idle. Some times it is smooth. Only at idle. Smoothes out as soon as i accelerate. It has a 4.2 v6, automatic
with 101,000 miles. plugs replaced at 85,000.
-- Message posted using http://www.talkaboutautos.com/group/alt.autos.ford / More information at http://www.talkaboutautos.com/faq.html
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Check the Idle Air Compensator (IAC) motor. It's normally on the throttle body somewhere (NOT THE THROTTLE POSITION SENSOR!!!). I had a 99 Ranger that did the same thing and I pulled the IAC off and loaded it down with carb and choke cleaner then put it back on. Voila!
It's not a cheap part to replace which is why I say try this.
Also, plugs were replaced but what about the wires? A bad wire can crap one out too.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.