Engine-Codes - Chevrolet - P0446 CHEVROLET

P0446 CHEVROLET - Evaporative Emission Vent System Performance

Repair Importance Level: 1/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

P0446 CHEVROLET Possible Causes

  • Plugged vapor canister
  • Faulty vent solenoid
  • Pinched or blocked EVAP hose
  • Faulty FTP sensor

How is the P0446 CHEVROLET code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Tech Notes

Dirt and dust intrusion into the EVAP canister vent hose assembly, resulting in restricted air flow, may cause this condition.

There is a bulletin for the following models:
1999-2007 Chevrolet Silverado (Classic) Models
2007-2008 Chevrolet Silverado Models
Chevrolet Factory Service Bulletin OBDII Code P0446





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What is the cost to diagnose the P0446 CHEVROLET code

Labor: 1.0

The cost to diagnose the P0446 CHEVROLET code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
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When is the code detected?

The Powertrain Control Module (PCM) sets the P0446 code if the vacuum decay rate is greater than a predetermined value.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Possible a noticeable fuel odor caused by the release of fuel vapors

P0446 CHEVROLET Meaning

The Powertrain Control Module (PCM) monitors the performance of the Evaporative Emission (EVAP) system by applying a predetermined level of vacuum to the EVAP system then monitors the vacuum decay rate.

More Information

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