If you haven't downloaded the FSM for your truck yet do so. There are (2) adjustment screws for "idle" control. From the passenger side looking in, the one closest to the front of the truck is the idle control. The one towards the rear next to the vacuum diaphram is the fast idle screw adjustment. Just wanted to make that clarification because I had these two confused when I first got this truck and it was a little frustrating to say the least. Everytime I would turn the A/C on the truck would idle up to around 2k rpm. <img src="/forums/images/graemlins/lol.gif" alt="" />