I resently finished my first engine swap an LSVTEC into an integra. The engine starts up fine but idles just under 2000. Im currently using a obd1 gsr ecu with a jun chip from ebay. I also have a obd2 gsr ecu that will start the motor which also idle just under 2000 but once its heated up it "ruff" idle dropping from 2000 down to 400 and back up. Can anyone tell me what maybe the cause? And how to correct the idle.

 

check you vacum lines, sounds like you hava leak.

 

is ur car obd 1 or 2