OK, got out today in the currently tolerable weather and played with this thing some more. Tested every aspect of the FI system to rule that stuff out of the euqation. Air mass meter is within specs, fuel pressure is correct while running and sitting for 10 minutes (fuel filter is new), throttle switch is adjusted correctly. So, the symptoms that I am dealing with- car starts and idles fine, acceleration is a bit sluggish when rolling gently into the throttle. Falls flat on it's face and backfires under hard acceleration and under load. Ignition timing is set to factory spec and appears to advance when using a timing light in the driveway. I am still totally unclear how the timing advance is controlled (ECU???) and how load is sensed (normally manifold or ported vacuum on most cars, but apparently not this one). Any insight??? The ol' Haynes book is maginal at best.
Chris