P0496 Fault Code

Evaporative Emission System High Purge Flow

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

The P0496 fault code indicates an issue with the evaporative emission control system, specifically relating to high purge flow. This system is crucial for reducing emissions by capturing and recycling fuel vapors from the fuel tank, ensuring that harmful gases are not released into the atmosphere. High purge flow often points to a malfunctioning purge valve or leaks in the evaporation system that could lead to excessive fuel vapor flow into the intake manifold.

What are the symptoms of the P0496 code?

Common symptoms associated with the P0496 code may include:

• Check Engine Light illuminated on the dashboard.
• Poor fuel economy due to incorrect air-fuel mixture.
• Failed emissions tests at inspection stations.
• Rough idling or reduced engine performance in some situations.
• Evaporative system warning messages in some vehicles’ displays.

What causes the P0496 code?

Potential causes for the P0496 code can include:

• A stuck open purge valve, allowing too much vapor flow.
• Damaged or disconnected vacuum lines.
• Faulty gas cap that may not seal properly.
• Leaks in the evaporative emission system components.
• Trouble with the onboard diagnostic system that controls the purge flow.

How to fix P0496?

To resolve the P0496 code, the following steps are generally recommended:

• Inspect and replace the purge valve if found to be malfunctioning or stuck open.
• Check vacuum lines for signs of wear, damage, or disconnections; repair or replace as needed.
• Ensure the gas cap is in good condition and seals tightly; replace if faulty.
• Perform a smoke test on the evaporative system to identify leaks and address them accordingly.
• Clear the error codes after repairs and conduct a road test to ensure the issue is resolved.