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Diagnosis & Repair (Using Lexus Scan Tool)

  1. Check all EGR system vacuum hoses. Replace hoses as necessary and retest system. If vacuum hoses are okay, check EGR VSV. EGR VSV is located near air intake chamber assembly. Connect Lexus scan tool to DLC No. 3. See Figure. Using scan tool, select ACTIVE TEST mode and go to next step.
  2. Using scan tool, turn EGR VSV valve on. Apply compressed air to port "E". Air should flow from port "F". See Figure. Using scan tool, turn EGR VSV valve off. Apply compressed air to port "E". Air should flow from port "G". If valve operates correctly, go to step 6). If valve does not operate correctly, go to next step.
  3. Remove EGR VSV. Using ohmmeter, measure resistance between valve terminals. Resistance should be 27-33 ohms at 68°F (20°C). Measure resistance between each terminal and body of valve. Resistance should be infinite. If resistance is as specified, go to next step. If resistance is not as specified, replace EGR VSV.
  4. Apply compressed air to port "E" of EGR VSV. Air should flow from port "G". Using fused jumper wires, apply battery voltage and ground to EGR VSV terminals. Again, apply compressed air to port "E". Air should flow from port "F". Replace EGR VSV as necessary.
  5. If valve meets all specifications, check for an short in Yellow/Green wire between ECM E7 connector and EGR VSV. See appropriate wiring diagram in SYSTEM WIRING DIAGRAMS article. Repair as necessary.
  6. Disconnect vacuum hose from EGR valve. Start engine. Apply vacuum to EGR valve. If engine runs rough or stalls, go to next step. If engine does not stall or run rough, check EGR valve intake and exhaust passages. If passages are clean, replace EGR valve and retest system.
  7. Check EGR valve position sensor. See DTC P1410: EGR VALVE POSITION SENSOR CIRCUIT MALFUNCTION . If EGR valve position sensor is okay, replace ECM and retest system.
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