NoPistons -Mazda Rx7 & Rx8 Rotary Forum - Engine sputters under load

So, I just did an entire rebuild. Things looked pretty good after startup, good oil pressure, seemed to be ok, and I let it run for a bit. However, then the problems started. These all may or may not be related.

1. I have error codes 12 and 18. This is the Throttle Position Sensor. However it is hooked up just as it was before! what exactly will throw this code?

2. The car runs like crap as soon as you hit boost. It will buck like crazy, doesn't have any power, and is worst at low RPM. Higher RPM (above 6k) it will run smoothly but doesn't have any power.

3. The idle is around 500 and the car will actually die some times. Is this related?

4. It may or may not be missing every once and a while. I am not sure about this.

5. A much less important issue, I unplugged the smaller connector from CPU2 as my car currently thinks it is stolen. If it helps, my Viper locking system doesn't work either. This is low on the priority list, but if anyone has dealt with this before so I don't have to trace everything I would appreciate the advice.

Thanks