Troubleshooting the P0446 Code A Step-by-Step Guide for Mechanics

4) Take an air compressor and blow the vent valve out. 5) reinstall and clear the code and it's fixed. Now I know the updated part from gm is ... This generic OBD-II code indicates that the evaporative vent valve in the emission control system is malfunctioning. If the vent control circuit is throwing a code, the vent isnt opening to allow pressure release on fill up. Thus causing the fill neck to back ... P0446 Evaporative Emission Control System Vent Control malfunction. ... okay I got this same code recently and have not been able to figure ... It is most likely the valve in a line coming out of the gas tank. But they'd have to diagnose to know for sure, ie, supply power to the valve to see if it ... P0446 is a result of a test failure. The PCM closes the vent solenoid and opens the purge valve. It then monitors the fuel tank pressure sensor. I had a check engine light with P0446 code and no hiss when opening the gas cap so I started with changing the gas cap - no change It could be as simple as the gas cap not seating correctly or could be, like in my case, the fuel line was rusted and leaking pressure and gas. Chased around a P0446 code for a week and finally fixed it today. 1. Replaced gas cap - code came back 2. Replaced Vent valve - $30 - code came back 3. Took ... ... code is set when the computer (ECM/PCM) reads an issue with the vent valve, which is a part of the Evap system for emissions. The P0446 error ...