2017 Chevy Silverado 1500 P0446 EVAP Vent Control

2017 Chevy Silverado


  • 5.3L EcoTec3 V8 Engine
  • Horsepower: Approximately 355 hp
  • Torque: Approximately 383 lb-ft


  • 6-speed automatic transmission

Fuel Economy:

  • The EPA estimated fuel economy is around 16-18 MPG city and 22-24 MPG highway.

If you’re the owner of a 2017 Chevy Silverado with the 5.3L engine and you’re facing the diagnostic trouble code (DTC) P0446, it’s essential to understand this issue and take the right steps to address it promptly. This article will unravel the meaning of the P0446 code, shed light on its implications, and provide insights into effective methods for resolving it. The P0446 code is connected to the Evaporative Emission Control (EVAP) System Vent Control Circuit, and understanding it can aid in ensuring the optimal performance of your Silverado.

Understanding the P0446 Code:

The Engine Control Module (ECM) triggers the P0446 code, a Diagnostic Trouble Code (DTC), when it detects a problem with the EVAP System Vent Control Circuit. This circuit is responsible for controlling the release of fuel vapor into the atmosphere. The P0446 code specifically points to a blockage or malfunction in the EVAP canister vent solenoid, which can disrupt the proper management of fuel vapors.


Possible Causes of P0446 on a 2017 Chevy Silverado:

  • Faulty EVAP Vent Valve: A malfunctioning EVAP canister vent solenoid can prevent proper vapor release, leading to the activation of the P0446 code.
EVAP vent solenoid

A vehicle’s EVAP Vent Solenoid, a critical component of the Evaporative Emission Control (EVAP) system, plays a vital role in managing fuel vapor emissions and preventing their release into the environment. The opening and closing of the vent valve, which directs fuel vapors from the fuel tank into the engine for combustion rather than letting them escape into the atmosphere, is controlled by the EVAP vent solenoid.

  • Clogged Vent Line: Blockages or clogs in the vent line can hinder the release of fuel vapor, triggering the code.
  • Faulty Charcoal Canister: A malfunctioning charcoal canister can prevent proper vapor storage and release, causing the P0446 code to appear.

Steps to Diagnose and Resolve P0446:

  1. Visual Inspection: Begin by visually inspecting the EVAP canister vent solenoid, vent line, and the charcoal canister for any visible signs of damage, corrosion, or clogs.
  2. Test EVAP Vent Valve: Using a multimeter, test the resistance of the EVAP canister vent solenoid. Compare the readings to manufacturer specifications. Replace the valve if it falls outside the recommended range.
  3. Check Vent Line: Inspect the vent line for any blockages or clogs. Clear any obstructions if necessary.
  4. Check Charcoal Canister: Examine the charcoal canister for signs of damage or contamination. Clean or replace it as needed.
  5. Diagnostic Scan: Perform a diagnostic scan using a professional OBD-II scanner to retrieve specific data related to the P0446 issue. This can help pinpoint the exact source of the problem.
  6. Clear Codes and Test: After addressing the issue, use the OBD-II scanner to clear the P0446 code. Conduct a test drive to ensure the code doesn’t reappear and that the vehicle’s performance remains optimal.

The P0446 code on a 2017 Chevy Silverado highlights a potential problem within the EVAP System Vent Control Circuit. Addressing this issue promptly is essential for maintaining emissions compliance and preventing further complications. While some initial troubleshooting can be done, consulting a qualified Chevy mechanic for thorough diagnostics and repairs is recommended. Regular maintenance and attention to engine codes can contribute to a smooth and environmentally-friendly driving experience in your Silverado.

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