P0446 - Purge or Vent Solenoids Defective

nvrnuf4me · March 10, 2015

All,

My check engine light came on last night when I started my truck to go home from work. The code it's throwing is P0446 - Purge or Vent Solenoids Defective. I need some advise as I would not expect this on a truck that is only 13 months old. BEFORE anyone advises, take it to the dealer, I have 40k miles and am outside of the bumper to bumper. Also, my wife took the truck to the dealership this morning with a print out from Autozone showing the code and failure description. The service writer told her that it would not be covered under the 100k warranty. So, I need advise on what to look at and possible fixes. I have read online where some folks were shelling out close to $1000 to have dealers diagnose / fix this issue only to have it come back, but most of those were on 2000 to 2007 Chevrolets. I cannot find any information pertaining to the K2 style. Any help would be greatly appreciated!!!!!!!

If it matters, I live on a dirt road, only use Top Tier gas from Chevron / Valero, and only used E85 through 2 tanks.

FYI...2014 Silverado, 5.3

2007silveradonbs · March 10, 2015

Vent and Purge solenoids may be considered considered major emissions components. The major emissions component warranty is beyond the bumper to bumper warranty. You may want to see if they covered.

Crash1 · March 10, 2015

kstruckcountry · March 10, 2015

Vent and Purge solenoids may be considered considered major emissions components. The major emissions component warranty is beyond the bumper to bumper warranty. You may want to see if they covered.

This.

Also not sure how it is set up on the new pickups, maybe they moved the evap intake to the dustiest part of the pickup again.

newdude · March 10, 2015

DTC P0446: Evaporative Emission (EVAP) Vent System Performance.

Voltage test the fuel tank pressure sensor for certain voltages in certain conditions.

Smoke test the evap system to find a leak.

Could be a bad EVAP canister, a bad EVAP vent valve or a bad fuel tank pressure sensor. $100 to $250 for the part.

My opinion? Before $450 gets spent on parts, I'd take it to a dealer/repair shop and pay the hour diag and have the system tested.

Those above chiming with select component stuff, it varies.

Car or Light Duty Truck with a Gross Vehicle Weight Rating (GVWR) of 8,500 lbs. or less
2 years or 24,000 miles and 8 years or 80,000 miles for the catalytic converter, vehicle/powertrain control module, transmission control module or other onboard emissions diagnostic device, including emission-related software, whichever comes first.

So, from looking at some stuff, vent valve and purge valve are under the 2/24 emissions. If it is a PZEV state truck then it falls under the PZEV warranty. I ran a couple Texas trucks and none of them had PZEV so 2/24 would most likely be it for emissions coverage.

Edited March 10, 2015 by 15HDriver

nvrnuf4me · March 10, 2015

Thanks for the replies.

I spoke to the service advisor directly and he checked the system while I was on the phone. The Vent and Purge solenoids are not considered major emissions components and therefore, will not be covered under warranty. It would appear to me that the testing / diagnosis is going to be well worth the $50.00 flat rate fee they quoted. Will update when I know more. But, if anyone else has any more ideas, I am certainly willing to listen!

2007silveradonbs · March 10, 2015

You are 4K miles out of the bumper to bumper. See if the divisional manager will cover it anyway.

irish4life8911 · March 10, 2015

If there is any leak in the vacuum, it will throw that code. Did you leave your gas cap off or loose? Did you get fuel while your truck is running? Any of these can throw that code.

You can crawl under your truck and visually look at the components. There is a vent hose that goes from your fuel door to the evap emission canister, well at least one of them. Then you can follow the other hose to the front of the truck for the control valve. Not hard to replace, I had to replace all of them on my '05. Just time consuming

If it's a small leak, you can reset the cel and it won't come back on for a few weeks. It won't hurt your motor at all, worse thing that will happen is that you will let some vapor in the air

Edited March 10, 2015 by irish4life8911

patriot · March 10, 2015

Looks like you've got lots of helpful input, but one caveat:

STOP using Valero. It's crap gas.

nvrnuf4me · March 10, 2015

Looks like you've got lots of helpful input, but one caveat:

STOP using Valero. It's crap gas.

I only used Valero on a recent road trip. I am an exclusive Chevron user. However, I really do not want to start the fuel debate in yet another thread, there are plenty of them already.

Thanks for taking the time to read and post though, it is appreciated.

tbarn · March 11, 2015

Kinda on the wrong track.

This DTC tests the evaporative emission (EVAP) system for a restricted or blocked EVAP vent path that would cause excess amounts of vacuum to be developed in the EVAP system. The engine control module (ECM) commands the EVAP purge solenoid valve Open and the EVAP vent solenoid valve Closed. This allows vacuum to be applied to the EVAP system. Once a calibrated vacuum level has been reached, the ECM commands the EVAP purge solenoid valve Closed and the EVAP vent solenoid valve Open. The ECM monitors the fuel tank pressure (FTP) sensor for a decrease in vacuum. If the vacuum does not decrease to near 0 in H2O in a calibrated time, this DTC sets.

Most likely plugged vent solenoid given where you drive.

jamin87ss · March 13, 2015

Just got my truck back from dealer for several updates and she's light, u guessed it is this code they had to order me part, apparently this is becoming a common issues he told me water seems to be getting into these, I am not familiar with what it where this part is but it first happen while I was washing the truck, then again on a super damp morning after I cleared it myself the first time thinking it was the gas cap

Crash1 · March 18, 2015

What part did they order?

jamin87ss · March 18, 2015

looks like this is it,

http://www.ebay.com/itm/GM-OEM-Vapor-Canister-Solenoid-22840971-/251664604584

MrgsZ71 · November 21, 2015

Nvrnuf4me did you ever find your solution? I also have a 14 with the 5.3 that is out of the bumper to bumper. Same code just popped out on mine last night and just now starting to research. Thought this may be a good place to start.