2002 Explorer Limited V8 idle stall

I have just developed a problem after an evening start where the engine will stall at idle. At speed the engine and car appear to function normally, but I have to force higher RPM to keep from stalling. Is it a vacuum problem, sensor or something else?

I had same problem with my early production 2003 V8. The car stalled at idle (waiting for parking space) even when warm and for no apparent reason. I would stop and suddenly look down at dash and notice the idiot lights are on. This V8 runs really quiet. Took it to Ford and they flashed the PCM and since then no problem. They should have a TSB on this. This is one of those problems where a code may not be stored. It you're still under warranty you're covered. Otherwise my 03 is a great car.