I've had this problem a while now and it seems quite random. All I know is that when I accelerate from a stop it hesitates only when I floor it or push on the pedal rapidly. If I slowly accelerate no problem. I'm in the process of replacing vacuum hoses on the car but I really haven't found a leak. My idle is normal. I set it using the adjustment screw and it hasn't change much in the past 6 months since the last time I set it. I recently had the fuel pressure regulator and fuel filter plus fittings replaced as I had a severe leak. The problem was there before that and after. Car runs normal when driving and normal idling. Could it be a timing issue? I'm really confused. I did notice the car drops RPM rapidly when I disconnect and plug the vacuum hose that does to the pcv system ( at the flame trap). I plugged both ends. It seems like it doesn't react fast enough when pushing hard on the pedal. Also if I do this at speed say 60km/hr and acclerate to 100 no hesitation. My top speed hasn't changed either. So no loss of power there.

Thanks in advace
Chris