Had been having an acceleration issue , solved it by replacing rocker arm actuator, engine jumped the timing chain a few months later, replaced with engine from Japan. Had to modify somewhat by swapping engine mount,power steering pump,couple other parts including the actuator. The actuator plug on the recent engine had two plugs, the original on my ‘04 has one,swapped it out ran great a couple days and started cutting @2500 rpms. Not sure what year the ‘new’ engine is but were changes made in the rocker arm assembly in 05 or 06 that might cause this? I suppose the actuator may have gone bad,seems unlikely, and the current engine only has 53,000 miles on it.
Thoughts? Thanks,Steve

 

Welcome to the forum. Have you bled your cooling system at the bleed valve. Have you reset your Ecu.