P0446 on a 2017 Toyota Camry
EVAP Vent Control Circuit Fault
What does P0446 mean on a 2017 Toyota Camry?
P0446 is set when the engine control module detects that the EVAP vent valve circuit is not behaving as commanded. The vent valve is the normally-open solenoid that lets the charcoal canister breathe — and closes during the EVAP leak test to seal the system. P0446 typically means the vent valve is stuck (mechanically or electrically) so that the system can never seal properly for the leak test.
Symptoms on a 2017 Toyota Camry
- Check Engine Light is illuminated
- Difficulty filling the fuel tank (pump clicks off repeatedly)
- No other drivability problems
- Vehicle will fail emissions / smog testing
- Sometimes accompanied by P0455 (large leak) on the same scan
Likely causes on a 2017 Toyota Camry
- Failed EVAP vent valve / vent solenoid (mechanical sticking) Most commonEstimated repair: $80– $350
- Dirt, debris, or spider webs clogging the vent valve filter CommonEstimated repair: $20– $100
Common on trucks and SUVs with the canister mounted under the vehicle.
- Damaged wiring or connector at the vent valve CommonEstimated repair: $50– $250
- Failed PCM driver circuit for the vent valve (rare) RareEstimated repair: $400– $1,500
- Cracked or saturated EVAP charcoal canister OccasionalEstimated repair: $200– $600
How to diagnose this on a 2017 Toyota Camry
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Locate the vent valve on this vehicle
The vent valve is mounted on or next to the charcoal canister. On most modern trucks and SUVs that is behind the rear bumper or near the fuel tank. On many cars it sits in the engine compartment. Consult the service manual for the exact location.
Tools: Vehicle-specific service information
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Test the vent valve electrically
Disconnect the valve connector. With the key on, check for battery voltage on the power side. Apply 12 V across the solenoid terminals directly — you should hear and feel it click. A solenoid that does not click is dead and needs replacement.
Tools: Multimeter, Test leads / jumper wires
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Test the vent valve mechanically
Disconnect the hose at the vent valve. Connect a hand vacuum pump. With the solenoid de-energized, the valve should let air flow freely (no vacuum holds). With 12 V applied, the valve should hold vacuum. A valve that holds vacuum at rest, or that leaks vacuum when commanded closed, is the problem.
Tools: Hand vacuum pump, 12 V test source
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Inspect for contamination
Trucks and SUVs frequently get spider webs, mud, or sand inside the vent valve filter on the canister side. Some vehicles have a dust filter that is replaceable; others integrate it into the valve assembly. Clean or replace as needed.
Tools: Compressed air, Replacement filter (if applicable)
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Confirm the canister itself is intact
With the vent valve removed, look into the canister port for cracked plastic, saturated charcoal (will smell strongly of fuel), or debris. A failed canister will cause repeated P0446 set events even after the vent valve is replaced.
Tools: Flashlight
Known Technical Service Bulletins for the 2015-2019 Toyota Camry
Manufacturers publish Technical Service Bulletins (TSBs) when a known issue affects a specific vehicle. These bulletins come from the NHTSA database for your Toyota Camry.
- ENGINE Feb 12, 2026
This bulletin includes basic procedures for performing a rescue charge on Ni-MH high voltage (HV) batteries. This bulletin should be used in conjunction with the applicable model and model year Repair Manual while performing a rescue charge. The GRX-5100 should be used wherever the Repair Manual references the Toyota Hybrid System (THS) charger.
NHTSA #11029893 - ENGINE Feb 12, 2026
OBSOLETE NOTICE February 13, 2026: This bulletin is now obsolete. Please see T-SB-0009-26.
NHTSA #11029892 - UNKNOWN OR OTHER Jan 6, 2026
Some 2005 – 2026 Toyota vehicles that have undergone water intrusion may exhibit a condition in which a musty odor is present. Follow the procedures in this bulletin to remediate the odor and address this condition. The purpose of this Service Bulletin is to provide general guidelines and procedures for odor remediation. This Service Bulletin provides a guide on how to prepare and treat the interior of the vehicle for odor remediation. Refer to the applicable model and model year Repair Manual and the EPA (Environmental Protection Agency) website for the most up-to-date safety and precautionary guidelines.
NHTSA #11028712 - ELECTRICAL SYSTEM Jun 12, 2025
The air conditioning dye injection tool kit has been developed to aid in identifying the location of air conditioning refrigerant leaks. The procedures outlined in this Service Bulletin aid in locating, inspecting, and repairing refrigerant leaks.
NHTSA #11020657 - STRUCTURE Dec 5, 2024
To prevent brake rotor rust from forming during transportation and storage, wheel film will be used instead of a cardboard type of anti-rust cover. The purpose of the wheel film is to shield the disc brake rotor from weather elements and initial rust before the vehicle is delivered to the customer. Consequently, the film should remain on the wheel for as long as possible.
NHTSA #11012743 - STRUCTURE Dec 5, 2024
The condition known as acid rain is caused by airborne chemicals or particles in the atmosphere, which mix with rainwater, nighttime dew, or high humidity to form acidic compounds. If these contaminants settle and remain on a painted vehicle surface, especially the horizonal areas of the hood, roof, and decklid, significant damage can occur. This damage is the result of actual etching of the paint and appears as pitting or water spots. As acid rain droplets on the vehicle surface evaporate, the concentration strength of the acid increases, causing deeper and more rapid damage. This evaporation and corrosive action also occur more rapidly on dark colored cars as direct sun heat increases. It is the dealer’s responsibility to protect and maintain the quality of the vehicle’s paint finish after receipt at the dealership prior to the first sale. In areas known for high frequency and/or concentration of acid rain, frequent vehicle washing during high heat or humidity periods will minimize the potential for paint damage caused by acid rain. It is further recommended that either reverse osmosis or deionized water be used to prevent water spotting.
NHTSA #11012744
+14 more TSBs available in MECH AI's TSB explorer for this vehicle.
Common fixes
- Replace the EVAP vent valve / vent solenoid
- Clean the vent valve filter and inspection port
- Repair damaged wiring or connector at the vent valve
- Replace the charcoal canister assembly
About the 2015-2019 Toyota Camry
The 2015-2019 Toyota Camry was commonly sold with the following powertrains: 2.5L I4, 3.5L V6, 2.5L Hybrid I4. Common trims include LE, SE, XLE, XSE.
Why the gas pump clicks off with P0446
The vent valve is what allows the fuel tank to “breathe” during refueling. If the valve is stuck closed, displaced air cannot escape as fuel goes in — pressure builds, fuel splashes back into the filler neck, and the pump nozzle’s auto-shutoff triggers prematurely. If you have to “trickle fill” your tank to get gas in, P0446 (or a related vent code) is the most likely cause.
When P0446 sets with P0455
If P0446 (vent control) sets alongside P0455 (large leak), the root cause is usually one part — the vent valve is stuck open, so the system can never seal for the leak test, which triggers both codes. Replace the vent valve and clear codes; if P0455 returns alone the next monitor run, do a separate small-leak diagnosis.
Trucks and SUVs vs. cars
Under-vehicle mounted vent valves (most trucks, SUVs, and minivans) fail more often than engine-bay mounted ones. They live in a worse environment — road spray, salt, mud, debris. On vehicles with chronic P0446, an upgraded “all-terrain” vent valve or a relocation kit is sometimes worth considering after the second failure.