Re: Rough Idle...No Check Engine Light on
I had the same problem on my '97 Explorer 5.0 V8. Sometimes it would barely idle and stall out unless I kept a foot on the accelerator while at a stop. This seemed to happen only on cold and/or wet mornings, and the problem would go away as the engine came up to normal temperature.
I removed the Idle Air Control valve (IAC, on top of the intake manifold, righthand side; 2 10mm bolts). The valve plunger and return spring had a lot of dry black carbon deposits. It was very hard to move the valve with a pair of needle nose pliers. Since a new valve is upwards of $50, I tried something cheap and simple: WD-40. After lubing up the shaft and spring and letting it sit about 10 minutes, I worked the valve back and forth a few times with pliers (it moved very easily now) and reinstalled the valve (with some high temp silicon RTV on the gasket, which had cracked on removal).
That was about a month ago and the problem seems to have gone away, despite some very cold, wet and even icy conditions since.