Originally Posted by RedRanger02
ill have to give that a try... is that like an idle ajustment screw? if so will it screw up the way the truck runs when it is running right?
It's more of a travel stop for the butterfly in the throttle body. Since the idle speed is determined by the EECM, any change to the throttle body will be compensated for by the engine computer. Depending on how large of an adjustment you make, the time for the computer to adapt may be transparent.
For example, I have to adjust my throttle body every winter because the throttle body sticks closed (thanks to the expert service from my local dealer), and it usually doesn't change the engine RPMs at all. The first time I made an adjustment, I had to turn the screw down far enough that the engine did idle fast, but the EECM "learned" the new air flow, and lowered idle speed accordingly.
I hate to throw parts at a problem without knowing the actual cause, but here's a suggestion. I had always heard that when you have a rough idle problem, especially one that is intermittent, the problem may lie in the spark plug wires. I know you only have 35,000 miles, but if you can't find any other possible causes, it might be worth a try.
Keep us posted on how it turns out.
EDIT: You say the rough idle only lasts for 1/4 second after starting. Mine does the same thing too, but lasts for a couple of seconds. It's only on a cold start, when the ambient temperature is below about 50 degrees Fahrenheit. It idles rough, and hangs at 1000 RPM for a couple of seconds. It smooths out and climbs to the 1500 RPM cold idle and everything is fine. It's done this from day one. After four years, I've learned to live with it. The dealer can't fix it, and the powertrain engineers on Ford's service hotline say that although it's not normal, it's not a problem.
I've read other threads where guys have suggested changing or cleaing the the MAF sensor, replacing the air intake temperature sensor, coolant temperature sensor, idle air control, or throttle position sensor. I wouldn't go that far, but if you can check the voltage output from each sensor on a cold start and compare that to the tolerances allowed by Ford, you might get somewhere.
My bottom line is that I have read a lot about the problem as described in my EDIT, but have yet to find a definitive solution. Good luck.