I know that this code is an emissions venting problem that can be associated with the gas cap, vent valve, charcoal canister, control circuit, power circuit and/or the PCM. About a month ago I filled up and forgot to shut the engine off while filling. No issues at the time. Presently, about a week ago my engine icon came on. I connected my OBD tester and found no codes and it also stated that the MIL was off even though it wasn't. I reset or rebooted the icon by disconnecting the battery. I recently filled up again and the nozzle kept shutting off, a real pain. This seems to point to a venting problem. A couple of days goes by and the icon is on again and now the tester shows the 446 code and the MIL is on.

So, what do you guys and gals think? My HHR Panel is only 3yrs old with just over 17K miles, local driving only. Should I try a new cap? Did the filling with the engine running cause a delayed issue? Any advice would be appreciated before I decide to bring the car in for service.

 

Delayed issue for engine running while filling....forget it.Anyway,p0456 is just a small leak...I am a mechanic and the most common repair for this dtc is the vent control solenoid.In my troubleshooter tool,i see many case of small leak on this solenoid.Hope this will help you.

 

A new gas cap will only cost about $9 go for it! The rubber gasket does go bad with time, mine did.

 

Thanks for the quick replies. I will look into the solenoid and also the cap.

 

It's not the gas cap and I do think this is a clog not a leak since I had trouble filling the tank at the gas pump. I'll let the dealer figure it out since this should be covered under the emissions warranty, I hope.

 

@Felony, I can see how frustrating this must be for you. Please, let me know what the dealership comes up with.

I hope you have a great weekend.

Michelle, Chevrolet Customer Service

 

Took me a while to get the car to the dealer. As ecopower ss surmised, the solenoid for the valve was sticking. $323 later, fixed. Not covered under the 8yr 80K warranty and my car is 2mo over the basic warranty. I am not pleased that this repair was needed with less than 18K miles on a 3yr old car. I am not pleased that the emissions warranty only covers the cat and flex pipe if I am correct. Not pleased that the dealer said there is some pulsing in my brake pedal and that the front rotors are slightly warped and need resurfacing after 18K. This car is just driven locally and not aggressively at all. I now know just how cheap this car really is. Not going to be a long term keeper for me. Sorry for the polite rant, but I've owned a great number of cars and for a car built in '09 to need work after 18K easy miles, needing the rear wiper motor replaced in the first month of ownership, the shaved doors not opening properly as well, is too much for me.