intermitent no spark

1998 Windstar 3.0 Driving one, van stops running. Test coil, CPS,PCM relay,etc. Coil pack was out of spec, replaced, new. sparkplugs out of spec. replaced,new. one plug wire broken, replaced, new. No spark,data link error on pocket scanner. PCM replaced, used, all numbers match came from same type Windstar,verified by VIN. Starts 6-8 times drive twenty feet, dies, no spark.Retest, OK back to square one.Dissconnect PCM for twenty minutes, reconnect, starts fine. Drive around parking lot and all is fine, two hours later, no spark.

Can anyone help? I am running out of hair!:banghead:

PCM power Relay....located in the engine compartment fuse box
Less likely....but possible, Radio Interference Capacitor, mounted next to the coil pack....on the +12V in line (red with green stripe wire).

Other things that could be an issue, Camshaft Position Sensor, Crankshaft Position sensor and Constant Control Relay Module (CCRM).