P0498 Fault Code

Evaporative Emission System Vent Control Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0498 fault code indicates a problem with the evaporative emission system, specifically relating to the vent control circuit being low. This circuit is essential for regulating the pressure within the fuel tank and ensuring that vapor emissions are controlled and directed back into the engine to be burned. When this circuit doesn't operate correctly, it can lead to excessive emission of fuel vapors, impacting both performance and environmental standards.

What are the symptoms of the P0498 code?

• Check engine light illuminated
• Fuel tank pressure issues
• Difficulty starting the engine after refueling
• Reduced engine performance or fuel efficiency
• Unexplained fuel leaks or vapor smells near the gas cap.
• Emission test failure.

What causes the P0498 code?

• Malfunctioning vent control valve
• Damaged wiring or connectors in the vent control circuit
• Short or open circuit in the wiring harness
• Faulty engine control module (ECM)
• Blockage or damage in the evaporative emission system
• Poor ground connection in the electrical system.

How to fix P0498?

• Inspect and replace any damaged wiring or connectors.
• Test the vent control valve for proper operation and replace it if necessary.
• Check for blockages or leaks in the evaporative emission system components.
• Clear the fault codes and perform a drive cycle to see if the code returns.
• If all components are functional, consider testing or replacing the ECM.