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Error Code P0497

Low Issue
DTC Code P0497 indicates an Evaporative Emission System Low Purge Flow issue. This occurs when the Engine Control Module (ECM) detects pressure in the EVAP system during a non-purge condition, suggesting the Purge Control Solenoid Valve (PCSV) is not operating within factory specifications.

What symptoms indicate Error Code P0497?

  • Engine Light ON: The check engine light or service engine soon warning light illuminates on the dashboard, indicating a potential issue with the evaporative emission system.
  • Reduced Fuel Efficiency: Drivers may notice a decrease in fuel efficiency due to improper fuel vapor management, which can be linked to low purge flow in the evaporative emission system.
  • Rough Idle: The vehicle may experience a rough idle, which can be associated with an imbalance in the air-fuel mixture caused by low purge flow.
  • Increased Emissions: There may be an increase in emissions due to the evaporative emission system not functioning optimally, leading to potential environmental concerns.

What causes OBD code Error Code P0497?

  • The Purge Control Solenoid Valve (PCSV) may be malfunctioning, leading to inadequate control of the purge flow in the evaporative emission system.
  • An open or shorted harness in the PCSV can disrupt the electrical signals necessary for proper valve operation, causing low purge flow.
  • Poor electrical connections in the PCSV circuit can result in intermittent or insufficient power supply, affecting the valve's ability to regulate the purge flow effectively.

How to fix OBD code Error Code P0497?

  • Check Technical Service Bulletins (TSB): Review TSBs for known issues and fixes related to P0497 for your vehicle model.
  • Perform Visual Inspection: Inspect all system wiring, connectors, vacuum lines, and hoses for damage. Repair or replace as necessary.
  • Use Smoke Machine for Leak Detection: Utilize a smoke machine to identify leaks in the EVAP system. Ensure vacuum lines are plugged before applying smoke.
  • Retrieve and Record Codes: Connect a diagnostic scanner to retrieve stored codes and freeze frame data. Record this information for reference.
  • Clear Codes and Test Drive: Clear all codes and conduct a test drive. Monitor if the code resets after several ignition cycles.
  • Test EVAP Purge Solenoid/Valve: Consult the service manual for specifications. Use a scanner to activate the solenoid and check vacuum flow with the engine running.
  • Check Voltage and Ground Signals: If the solenoid fails to open, verify system voltage and ground signals against manufacturer specifications.
  • Inspect System Circuits: If voltage and ground signals are absent, disconnect controllers and test circuits with a DVOM. Repair or replace as needed.
  • Evaluate PCM: If all components meet specifications, consider a defective PCM or programming error.

Similar OBD Codes

P0440

Evaporative Emission Control System Malfunction

P0441

Evaporative Emission Control System Purge Flow Issue

P0443

Evaporative Emission Control System Purge Valve Circuit Malfunction

P0446

Evaporative Emission Vent System Performance Issue

P0449

Evaporative Emission Vent Solenoid Valve Circuit Issue

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