Hyundai: 2001 Hyundai Sonata P0446, emission control system, hyundai sonata

Question
Hello. I am getting the P0446 code but it only seems to occur if I hit 80mph. I can clear the code and it will be fine through normal driving but if I hit the highway almost the instant I hit 80 my check engine light will come on and sure enough when I pull the code it is P0446, no other codes. It runs and idles fine otherwise. Does it make sense for that code to be seemingly related to speed? Would the CCV valve be the fix? Any thoughts would be greatly appreciated. Thanks!

Answer
Hi Vince, well the P0446 code mean Evaporative Emission control system Vent control circuit. Look for a disconnectted or damaged hose around the air filter box that goes the evap solenoid, sometimes it's gets knocked off when servicing the air filter, solenoid could be failed, the cannister could be breaking down and causing the evap solenoids and valves to stick. can be a trickier system to diag because there are lots of components in the system.