Intermittent Engine Stalling '01 Windstar

[windvane]

My 01 Ford Windstar SEL intermittently stall particularly when accelerating. I'll just turn off the key, shift to neutral and restart again. When running on constant speed it never happen, only when I step on the pedal hard enough. But if the car is not moving (neutral) even if I step on gas hard it's okay. No CEL message. NO error code in OBD II. Cam position sensor, Coil, Fuel filter were already replaced. I tried almost everything, clean MAF sensor, put injector cleaner, change to premium gas, still stalling happens. Could it be the trouble in PCM? Please help.