System Check - EGR

CIRCUIT DESCRIPTION:
To control Exhaust Gas Recirculation (EGR), the PCM operates the linear EGR valve. The linear EGR valve is a small motor with a pintle that is normally closed. By providing a ground path, the PCM will open the pintle and allow exhaust gasses to pass through the valve. The PCM control of the EGR is based on the following inputs:
^ Engine coolant temperature - above 25° C.
^ TP - "OFF" idle.
^ MAP.
^ IAT, if equipped.
^ BARO.
^ PRNDL position switch.
^ Pintle position sensor.
If DTC 23 is stored, refer to CODE 23 INTAKE AIR TEMPERATURE SENSOR CIRCUIT.
If DTC 32 is stored, refer to CODE 32 EXHAUST GAS RECIRCULATION CIRCUIT. Powertrain Controls - ECM/PCMThis chart is used for faulty valve, plugged EGR passages, or improper wiring connections.

CHART TEST DESCRIPTION:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. At idle, the EGR valve should not be open greater than 3%. A misadjusted Park/Neutral Position (PNP) switch or the EGR valve stuck open will allow exhaust gasses to enter the combustion chamber and create a rough idle condition.
2. Checks the pintle's ability to be manually commanded to the desired positions.
3. Checks the electrical circuit of the EGR valve and connecting components.
4. Checks for plugged EGR passages or a faulty EGR valve.