aEROz & hitz:
Hey both of you, it has been a while. Well the symptom that you guys describe does point to certains possibilities like fuel filter not giving smooth passage anymore. You see, my car does not have any fuel filter attached and I never had this problem. But I have seen on a customer's MIVEC Blacktop before that the pressure will fluctuate simply becoz the fuel filter is old and dusty (literally got dust inside when opened and inspected).
Another one is vacuum stability. To know if the vacuum is good or not, simply disconnect the vacuum off from the A-FPR and monitor the Pressure Gauge, it should be stationary without any vibration at all (full throttle setting). If with vacuum off oso vibrate then the Fuel Pump is dying or strong indication of fuel filtiration un-evenness.
Worst case scenario, if you guys have time we set up a meeting or you guys can go to the workshop that I am renting now (map below) after 6PM till late night.
http://img.photobucket.com/albums/v645/EFN/Workshop.jpg
Cheers there my frens