2011 LS 2.2 auto, 41K miles, check engine light alerts.

Spouse takes it to Auto Zone, they read code P0449 (Evaporative Emission EVAP Vent Solenoid Control Circuit, I understand) and they suggest buying and installing a Duralast #PV443 Canister Purge Valve, $23.99 plus tax.

I take to dealer, they read P0446 ("Evaporative Emissions (EVAP) Vent System Performance") and prep me for all kinds of bad news, insist it probably is not covered under the emission system warranty, which should be still in effect.

Remote start won't work, presume this is related and will resolve with underlying issue.

Thoughts?

UPDATE 2/23/16 - THANKS FOR ALL THE GREAT IDEAS! Dealer possibly mistaken w P0446? Only thing tried so far is independent garaged cleared reportedly intermittent P0449 and it came right back. Gasket on fuel cap looks pretty good.

UPDATE 3/3/16 - Thanks again for all the tips. EVAP fuse was fine. Corrections at (purge?) valve under hood looked clean and gunk and corrosion-free. Have no garage, and it was snowing, so I put myself at dealer's mercy. It was indeed P0449, first service rep is dyslexic or something. Both valves were good, but they found corrosion in the harness near the connector under the car at (vent?) valve. Repaired harness. Mystified as to cause of corrosion, car has seen little salt and only 41K miles. Possibly slight fuel vapor leak through valve to wiring? Will keep an eye on it. Remote start works again :-) All is well for now.

 

https://www.chevyhhr.net/forums/how-...acement-44780/

One code might cause the other.

The nomenclature is very confusing, and every parts book uses different words. Basically the one under the hood lets the intake manifold suck fuel vapors in. The one near the gas tank lets air into the tank as you use fuel. It is more complicated than that.


Since you have both I'd start by looking at fuses, I think there is one marked EVAP.

You are lucky the 2011 already has the updated wiring harness for the vent solenoid, the one under the car. That would cost another $50 or so.


For the one under the hood:
Duralast/Canister Purge Valve PV443 - Read Reviews on Duralast #PV443

For the one under the car:
Duralast/Canister Vent Valve Solenoid PV483 - Read Reviews on Duralast #PV483

Don't worry that they say fits 2007 or something, all years are the same.

 

Try the under hood valve first, then clear the codes and see if that clears things up , the remote start will not function with a CEL light on

 

Yup the remote start is disabled when the CEL is lit.

For the P0449 - check this link - https://www.chevyhhr.net/forums/prob...49-code-20547/

The p0446 might be related, or it can be something as simple as the gas cap not tightened enough, or it's gasket is going bad. check this link - https://www.chevyhhr.net/forums/prob...or-code-42843/

this will probably help - https://www.chevyhhr.net/forums/how-...acement-44780/

 

Sometimes topping up the gas tank after the auto shut off can cause this issue

 

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.

 

See edits to Original Post for updates and solution.

 

Thanks for the update, yes keep an eye on it. It could be corroded for a number of reasons