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P0446MinorEmissions

P0446: Evaporative Emission Control System Vent Control Circuit

16 vehicles · 8 makes · $20-$2,500 repair

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P0446 is an OBD-II diagnostic trouble code meaning “Evaporative Emission Control System Vent Control Circuit.” Electrical fault in the EVAP vent control valve circuit. The vent valve controls airflow into the EVAP canister. This code appears across 16 vehicle models from 8 manufacturers, with repair costs ranging from $20 to $2,500.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (16)
  • Related Codes
  • FAQ

Makes

  • Chevrolet3
  • Chrysler1
  • Dodge1
  • Ford1
  • Kia2
  • Mazda2
  • Nissan2
  • Toyota6
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Common Causes

1Faulty vent valve
2Blocked vent filter
3Wiring issue
4Spider webs or debris blocking vent
5Corroded connector

Typical Repair Cost

$20 - $2,500

Based on 18 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0446, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (16)

Silverado 1500Minor

EVAP Vent Solenoid Clogging With Dust/Water Causing Check Engine Light and Hard Refueling

2000-2007$120-$4500 reports
ColoradoMinor

EVAP Vent Valve and Charcoal Canister Dust Ingestion Causing Check Engine Light and Hard Refueling

2004-2012$120-$6000 reports
SuburbanMinor

Rear AC System Failure and Refrigerant Leaks

2007-2020$200-$1,5000 reports
300Minor

EVAP System Small Leak (P0456)

2011-2023$20-$5002,800 reports
JourneyModerate

AC Compressor Failure and Evaporator Leaks

2009-2020$500-$1,800320 reports
FocusMinor

Canister Purge Valve Failure Causing Rough Idle and Hard Start

2012-2018$20-$1500 reports
RioModerate

A/C Compressor Premature Failure

2012-2018$500-$1,500289 reports
RioMinor

Evaporative Emissions Leak from Deteriorated Purge/Canister Hoses and Loose Fuel Filler Neck Components

2001-2011$40-$4500 reports
Mazda5Moderate

A/C Evaporator Core Leak

2006-2015$800-$1,800600 reports
Mazda3Moderate

EVAP Purge Valve Failure and Fuel Odor

2014-2018$80-$2500 reports
QuestMinor

Rear A/C System Failure

2011-2017$400-$1,500290 reports
FrontierMinor

EVAP Canister and Vent Control Valve Failure Triggering Check Engine Light

2000-2004$100-$6000 reports
FJ CruiserModerate

A/C Compressor and Evaporator Failure

2007-2014$400-$2,5001,200 reports
TacomaMinor

A/C Musty/Mold Smell

2016-2023$20-$300620 reports
CamryModerate

EVAP Charcoal Canister / Vent Valve Failure Triggering Check Engine Light

2002-2011$250-$9000 reports
TacomaModerate

Evaporative Emissions Leak Faults from Charcoal Canister, Vent Valve, or Filler Neck Corrosion

2000-2015$80-$9000 reports
CorollaModerate

EVAP Charcoal Canister and Vent Valve Failure Causing Check Engine Light

2000-2008$250-$9000 reports
RAV4Moderate

EVAP Charcoal Canister / Vent Valve Failure Triggering Check Engine Light and Refueling Vapor Issues

2001-2012$250-$9000 reports

Related Codes (8)

P0440Evaporative Emission Control System MalfunctionP0441Evaporative Emission Control System Incorrect Purge FlowP0442Evaporative Emission Control System Leak Detected (Small Leak)P0443Evaporative Emission Control System Purge Control Valve Circuit01447EVAP System (VAG)P0401Exhaust Gas Recirculation Flow InsufficientP0402Exhaust Gas Recirculation Flow ExcessiveP0403Exhaust Gas Recirculation Circuit Malfunction

FAQ

What does P0446 mean?

P0446 stands for "Evaporative Emission Control System Vent Control Circuit." Electrical fault in the EVAP vent control valve circuit. The vent valve controls airflow into the EVAP canister.

What are the most common causes of P0446?

The most common causes of P0446 are: Faulty vent valve, Blocked vent filter, Wiring issue, Spider webs or debris blocking vent, Corroded connector. The specific cause varies by vehicle.

How much does it cost to fix P0446?

Repair costs for P0446 range from $20 to $2,500, depending on the vehicle and root cause.

Which vehicles are affected by P0446?

Au7o has documented P0446 across 16 vehicle models from 8 manufacturers: Chevrolet, Chrysler, Dodge, Ford, Kia, Mazda, Nissan, Toyota.

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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