If you want the answer that is equal to the amount of detail given...you have either no tune or a very poor tune. To get beyond that ppl need to know whether the PFC was ever used & you would need a wideband/datalogger to check the tune yourself.
If you bought used PFC for 2ZZ engine, probably that you have too different MAP setting than a standard 2ZZ engine.
If you reset the Currently Map, a "base map" in PFC always come back. So reset the PFC is the first thing to do.
Base Map is just enought to go to tuner shop. Don't be tempted to go full throttle .
If you runn bigger injectors or Turbo, you have to tune the "base map" against running too lean/rich.
Assuming you have the Datalogit, reset the PFC is the first thing to do. If it starts follow the learning procedure. If not log ADVANCED parameters and look at one called AFL-V. Make sure it changes while cranking. If you still have trouble I am off work in a few hours. Feel free to DM me your number and I can help out.