Beside the PCM is a solenoid that enables vacuum to suck open an actuator that allows some exhaust gas to flow into the intake air stream. Easiest way to plug it is isloate the small rubber tube sticking out from the solenoid (black box towards the rear of the PCM) and stick a screw up it, leaving the thin tube hanging free. Also heard of guys using a blanking plate and plugging the exhaust hose connector, or completely removing the body and actuator.
Either way
HTH
Ron