I had this on a Dodge V8.
Moisture had gotten in the fuel system and over time had caused rust particles to build up and plug an injector. It would pass enough fuel at idle and light throttle but hard throttle it would drop a cylinder.
I fixed it by removing the injectors and using carb cleaner with the extension tube ,blow the crap out of the input side of the injector.
edit to add
Change the fuel filter if you haven't already
Last edited by OTRtech; 01-19-2010 at 09:56 AM.