Electronic Linear EGR Valve

Exhaust Gas Recirculation (EGR) Circuit Check:

Exhaust Gas Recirculation (EGR) Circuit:

Circuit Description:
To control Exhaust Gas Recirculation (EGR), the ECM 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 ECM will open the pintle and allow exhaust gasses to pass through the valve. The ECM control of the EGR is based on the following inputs:

^ Engine coolant temperature - above 25°C

^ TPS - "OFF" idle

^ MAP

^ IAT

^ BARO

^ Park/Neutral switch

^ Pintle Position Sensor

If Code 23 is stored, Powertrain Controls - ECM/PCM
If Code 32 is stored, Powertrain Controls - ECM/PCM This chart is used for faulty valve, plugged EGR passages, or improper wiring connections.

Test Description:
Numbers below refer to circled numbers on the diagnostic chart.

1. At idle, the EGR valve should not be open greater than 3%. A misadjusted Park/Neutral (P/N) 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.