I assume the transmission is set to auto? If not, I would not recommend going full throttle in a high gear at low RPM in any car. It can cause bad harmonic distortion to the bottom end where the crank gets torqued in ways its not supposed to. If you are in auto, then it should quickly shift, and that sounds more like a transmission problem than engine problem? I have a 6MT, so I can't provide much other help.
Good luck and keep us informed!