Investigating P0446 on Your 2022 Lexus GX
A P0446 code on your 2022 Lexus GX 460 indicates an EVAP vent control circuit malfunction. The second-generation GX uses the J150 body-on-frame platform with the naturally aspirated 4.6L V8. Lexus uses a canister close valve (CCV) for EVAP vent control, shared with Toyota's proven truck architecture.
The Lexus basic warranty (4yr/50k) may still be active. The powertrain warranty (6yr/70k) provides coverage through 2028.
Clues and Symptoms
- Check engine light with P0446
- Fuel fill difficulty
- EVAP readiness monitor incomplete
- Possible fuel odor
Top Suspects
- Canister Close Valve (CCV) Failure (High Likelihood): The CCV controls vent airflow and can fail after years of service. Replacement costs $150–$280 if not warranty-covered.
- Purge VSV Malfunction (High Likelihood): The Vacuum Switching Valve sticks, disrupting EVAP flow in the V8 system. Replacement runs $130–$240.
- CCV Wiring or Connector (Medium Likelihood): Body-on-frame underbody routing exposes wiring to road conditions. Repair costs $80–$180.
- Charcoal Canister (Medium Likelihood): The V8's higher fuel vapor output can stress the canister. Replacement runs $220–$400.
- Gas Cap Seal (Low Likelihood): Worn seal. Replacement is $15–$35.
How to Investigate
Scan all codes. A Techstream scan at a Lexus dealer provides CCV and purge VSV commanded testing. For DIY, check the gas cap first. The GX's body-on-frame design makes underbody components accessible from below for inspection.
Warranty and Cost
The basic warranty (4yr/50k) may still apply. The powertrain warranty (6yr/70k) covers through 2028, and the federal emissions warranty (8yr/80k) through 2030. Out of warranty: $130–$400.
Safe to Drive?
Yes. P0446 doesn't affect your GX's V8 engine, transmission, full-time 4WD, towing capacity, or off-road capability.