problems after engine swap

[ShahMat]

i just finished my engine swap,a ZC vtec. When the car is cold RPM jumps on 1300-1500 up and down, when its hot RPM falls to 200-300, then when i push gas slowly and it comes to 1500 it stucks on that point till i push gas little more
what could be the problem. sorry if that issue covered already had no results in search

 

[ShahMat]

error code 1401 air circulation value blah blah don't remember exactly
wut that means

 

[AHHVTEC]

fix the code

 

[ShahMat]

fix the code

when i fix tha code and restarting the engine it apears again

 

[AHHVTEC]

then its not fixed, you have to fix the device that the code is talking about