P0446

EVAP System Vent Control Circuit

EVAP / emissions Generic OBD-II Low

What it means

P0446 means the ECM has found a fault in the electrical circuit or operation of the EVAP vent control valve — the solenoid that lets the charcoal canister breathe and seals it for leak tests. It won't change how the car drives; it's an evaporative-emissions fault that keeps the check-engine light on and will fail a smog check until repaired.

Low

Can I keep driving? Safe to drive — this is an emissions fault that won't affect how the car runs, but it keeps the check-engine light on and will fail a smog check.

Real-world scan data

Seen in

443

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0446 scans

P0010in 19.2% of scans

P0135in 19.0% of scans

P0141in 18.5% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Fails an emissions / smog test
Occasional fuel vapor odor near the vehicle

Common causes

Most likely first

Faulty EVAP vent control valve (solenoid)Likely
Blocked, dirty, or disconnected vent hose or canister filterCommon
Damaged or corroded wiring/connector at the vent valveCommon
Rarely, a failing ECMLess often

How to diagnose & fix

Work through it in order

Read freeze-frame data to confirm the code and conditions.
Inspect the vent valve connector and wiring for damage or corrosion.
Test the vent solenoid's resistance and that it clicks/actuates when commanded.
Check the vent hose and canister filter for blockage or dirt.
Replace the vent control valve if it fails testing, then clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0446?+

Yes — it's an emissions circuit fault and won't affect driveability. It will keep the light on and fail an emissions test, so fix it when convenient.

Can I just clear P0446?+

You can, but it will return once the ECM re-runs its EVAP self-test unless the vent valve or its wiring is actually repaired.

Read & clear P0446 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX