I have no throttle control and no codes are coming up. Truck will start and idle no problem. Hit throttle and release really quick, it will rev up and return to idle. Hit throttle and hold, it will rev stumble and die quickly. Push throttle slowly it will want to start to rev but die out quickly. Operating hyd's to rev it up is hit or miss. Changed out the tank a few times, regulator was clogged/gummed and stuck so it was changed. No help there. Changed the pre-filter and housing, no help there. Injectors and distributor are about 1 month old maybe 2. All fluids are good. Any help is appreciated.