Diagnosis & Repair (Using OBD-II Scan Tester)
- Remove EGR gas temperature sensor. Place sensor and a thermometer into a container of water. Heat container and check sensor resistance. If resistance is as specified, go to next step. See EGR GAS TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS table. If resistance is not as specified, replace sensor.EGR GAS TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS
Temperature°F (°C) Ohms 122 (50) 64,000-97,000 212 (100) 11,000-16,000 302 2000-4000 - Check for open or short circuit in wiring harness between EGR gas temperature sensor and ECM. See appropriate wiring diagram in WIRING DIAGRAMS article. Repair as necessary. If wiring is okay, go to next step.
- Check EGR valve. See SYSTEM & COMPONENT TESTING. Replace as EGR valve as necessary. If EGR valve is okay, replace ECM and retest.