Theory Of Operation

WARNING: This page is about a different variant/trim than selected.

The Intake Swirl Valve (ISV) Actuator is located under the Intake Manifold. The ISV Actuator is not accessible without removing the Intake Manifold. There is a short jumper harness from the ISV Actuator that can be accessed for perfoming checks of the main (Actuator) wiring harness. The ISV Actuator is used to simultaneously position two flap shafts (one for each engine bank). Each ISV flap shaft has three valves (one for each cylinder). The ISV Actuator is supplied with 12 Volts by the ASD circuit and is controlled by the Powertrain Control Module (PCM) using the Swirl Valve Control circuit which is Pulse Width Modulated (PWM). There are also two ISV Position Sensors which are separate from the ISV Actuator. They are mounted at opposing ends of the Bank 1 and Bank 2 ISV flap shafts. These Position Sensors are monitored by the PCM over the ISV Position Sensor 1 and ISV Postion Sensor 2 circuits. The Intake Swirl Valves are used to create turbulence in the air entering the combustion chamber which helps to reduce emissions.

There are two separate approaches used for this monitor: The Standard Heat-Up (SHU) and the Rapid Heat-Up (RHU). Fuel economy and emissions are improved when the engine is allowed to reach a higher temperature. Engine performance and torque are increased when the engine is running at a cooler temperature. The PCM determines which heat-up mode to use based on various conditions.

The PCM uses the P200A-00 monitor when there is an Intake Manifold Runner Performance occurrence during the SHU mode.

The PCM uses the P2D2D-00 monitor when there is an Intake Manifold Runner Performance occurrence during the RHU mode.

Because the PCM switches between SHU and RHU mode, both DTCs may be present when flow-excessive is detected. Both DTCs have the same Diagnostic content.