acc is your idle control valve im pretty sure (or its the iac), you will still need this if your running a standard ecu. in the manual it tells you how to adjust idle there's a little screw inside that valve and if the valve gets clogged with #OOPS# it will affect cold start and obviously idle speed, your sposed to clean it every so often. i would make sure your temp sensor is working properly and that there is no vacuum leaks, i wouldn't be touching the tps