Fault codes › P0499

P0499

Evaporative Emission System Vent Valve Control Circuit High

Generic code Auxiliary Emissions Control Low severity Hard repair
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iWhat P0499 means

  • The fault code P0499 indicates a high voltage condition in the control circuit of the evaporative emission system vent valve. This suggests an issue with the circuit responsible for controlling the vent valve, which is designed to regulate the flow of fuel vapors from the fuel tank to the charcoal canister. A high voltage reading can disrupt the proper functioning of the vent valve, potentially affecting the emissions control system.

!Possible symptoms

  • Check Engine Light illuminated
  • Possible fuel odor
  • Failed emission test
  • Irregular idle or stalling
  • Increased fuel consumption

?Possible causes

  • Faulty evaporative emission system vent valve
  • Wiring or connector problems in the control circuit
  • Malfunctioning charcoal canister
  • Blockage or restriction in the vent valve or canister
  • Faulty engine control module (ECM)

⚙Related parts

  • Purge Flow Sensor: This sensor helps to prevent fuel vapors in the fuel tank from escaping into the atmosphere. Problems lead to fuel loss

✓Possible solutions

  • Inspect and replace the faulty evaporative emission system vent valve, if necessary
  • Check for wiring or connector issues in the control circuit and repair as needed
  • Test and replace the malfunctioning charcoal canister, if required
  • Clear any blockages or restrictions in the vent valve or canister
  • Consider replacing the engine control module (ECM) if all components are functioning correctly
Free on OBD DashX

P0499 on OBD DashX

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