1jz misfire/cut out problems.
 

I'm not on here all that much, but I've got a problem I just can't seem to figure out. I swapped my 1jz about a year ago, ran great until about last week. Normal driving is fine, but at full throttle she misfires at 4200-4400, and then again at around 6k. Accross the band anywhere else it's fine, and if I give it say, 3/4 throttle, or anything under full throttle, she accelerates fine. I've checked the codes, and it's giving me three different ones.

41 (which is TPS, I know what this is from, I'm using a Soarer ECU with my supra components.)

47 (which is Sub throttle for traction control) I usually don't get this code, but it's there.

and 51 (which is knock sensor #1.)

I've checked all my voltages from my sensors and everything seems to be in range. I've replaced my knock sensor with no change, and checked the wire harness to make sure the signal is going from the sensor to the ecu which it is.

Could it be that my ECU is just going bad? Or could it be something different altogether, like a missing ground or something? Any help would be appreciated, cause I'm completely stumped. And I'll admit I'm no expert with this engine or supra's in general.