EGR System

OPERATION
Cold Engine - (coolant temperature: below 55°C (131°F1)
EGR operation is stopped to improve driveability when the engine is cold.




Warm Engine
The ECM controls the EGR solenoid valves (vacuum side and vent side) to supply EGR gases as described in chart.

SYSTEM TEST



1. Connect the SSTs to the ECM as shown.
2. Start the engine.
3. Drive the vehicle and verify that ECM terminals 2S and 2R voltage is battery positive voltage (B+) while the engine is still cold.
4. Warm up the engine to normal operating temperature.
5. Drive the vehicle and verify that the Engine Signal Monitor green and red lamps flash when the SST is set to 2S and 2R.
6. Stop the vehicle and let it idle.
7. Ground the ECM terminal 2R by using a jumper wire.
8. Verify that the engine runs roughly or stalls at idle.