P0446 on Chevrolet
Evaporative Emission Control System Vent Control Circuit
P0446 on Chevrolet vehicles indicates evaporative emission control system vent control circuit. Au7o has documented this code across 2 Chevrolet models — most commonly on Colorado, Silverado 1500. This emissions code points to a problem in the evaporative emission (EVAP) system's vent control circuit, which manages the vent valve that lets the charcoal canister breathe and seals it during leak tests. The EVAP system captures fuel vapors from the tank to keep them out of the atmosphere, and the vent valve must open and close on command for the system to work and self-test. The code sets when the engine computer detects an electrical or performance fault with this vent valve or its circuit. It usually causes only a check engine light with no driveability change, but it does prevent proper EVAP leak monitoring. Typical repair costs on Chevrolet range from $120 to $600, depending on the specific model and root cause.
Common Causes of P0446
- •Faulty EVAP vent control valve (solenoid)
- •Wiring or connector fault in the vent valve circuit
- •Vent valve clogged with dirt, debris, or spider webs
- •Damaged or corroded vent valve connector
- •Blocked or pinched vent hose or filter
- •Faulty charcoal canister assembly
- •Faulty engine control module driver circuit
P0446 on Chevrolet by Model
Chevrolet Colorado(1 issue)
- EVAP Vent Valve and Charcoal Canister Dust Ingestion Causing Check Engine Light and Hard Refueling2004-2012
First-generation Colorado trucks frequently develop EVAP system faults because the vent valve and canister are mounted in an area exposed to dust, dirt, and road debris. Contamination can clog the vent path or stick the valve, triggering a check engine light and causing the fuel nozzle to click off repeatedly during refueling. This issue is especially common on trucks used on gravel roads or in dusty environments.
Chevrolet Silverado 1500(1 issue)
- EVAP Vent Solenoid Clogging With Dust/Water Causing Check Engine Light and Hard Refueling2000-2007
A very common GMT800 Silverado problem is contamination of the EVAP canister vent valve/solenoid by dust, road debris, or water intrusion. When the vent cannot flow properly, the truck sets EVAP leak or vent performance codes and may repeatedly shut off the gas pump during refueling. GM issued service bulletins and updated vent relocation kits for trucks used in dusty environments.
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What does P0446 mean on Chevrolet?▼
P0446 stands for "Evaporative Emission Control System Vent Control Circuit." This emissions code points to a problem in the evaporative emission (EVAP) system's vent control circuit, which manages the vent valve that lets the charcoal canister breathe and seals it during leak tests. The EVAP system captures fuel vapors from the tank to keep them out of the atmosphere, and the vent valve must open and close on command for the system to work and self-test. The code sets when the engine computer detects an electrical or performance fault with this vent valve or its circuit. It usually causes only a check engine light with no driveability change, but it does prevent proper EVAP leak monitoring. On Chevrolet specifically, this code is documented across 2 models.
What causes P0446 on Chevrolet vehicles?▼
Common causes on Chevrolet: Faulty EVAP vent control valve (solenoid), Wiring or connector fault in the vent valve circuit, Vent valve clogged with dirt, debris, or spider webs, Damaged or corroded vent valve connector, Blocked or pinched vent hose or filter. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0446 on a Chevrolet?▼
Repair costs on Chevrolet range from $120 to $600, depending on the specific model and root cause.
Which Chevrolet models have P0446 documented?▼
Au7o has documented P0446 on 2 Chevrolet models: Colorado, Silverado 1500.