I have replaced several vent solenoid valves for codes p0449, p0442, p0446, p0440. P0442 is usually the first code to set for a small evap system leak. That leak is almost always due to gas cap or vent valve not completely sealing due to debris, water, etc. I would go with the vent valve first. Also, with the engine off during refueling, the vent valve is off and should vent to atmosphere. This allows air in the top of the tank to "vent out" to the cannister so the fuel will not "burp" back at you.

Joseph

 

#02-06-04-037I: Check Engine Light On, Fuel Tank Hard to Fill, DTCs P0442, P0446, P0455 or P0449 Set (Replace EVAP Solenoid) - (Sep 16, 2010)


Subject: Check Engine Light On, Fuel Tank Hard to Fill, DTCs P0442, P0446, P0455 or P0449 Set (Replace Evaporative Emission (EVAP) Vent Valve Solenoid Assembly and Add/Relocate Filter Box Using Service Kit)


Models: 1999-2007 Chevrolet Silverado (Classic) Models

1999-2007 GMC Sierra (Classic) Models

2007-2010 Chevrolet Silverado Models (Including Hybrid)

2007-2010 GMC Sierra Models (Including Hybrid)




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This bulletin is being revised to add the 2010 model year and to include the Hybrid models. Please discard Corporate Bulletin Number 02-06-04-037H (Section 06 - Engine/Propulsion System).


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Condition
Some customers may comment about the check engine light being illuminated. They may also comment that their vehicle is difficult to fill with fuel or when filling, the pump continuously shuts off before the tank is full.

When checking the vehicle for DTCs, the ECM may report one or more of the following DTCs set as current or in history: P0442, P0446, P0449 or P0455.

Cause
The EVAP canister vent solenoid (CVS) valve draws fresh air into the system through a vent.

Under certain operating conditions, dirt and dust intrusion into the EVAP CVS fresh air intake/venting system, may result in restricted air flow.

Under certain operating conditions, water, if ingested into the EVAP CVS fresh air intake/venting system, may reach the CVS valve causing corrosion in the CVS valve, and may cause restrictions in the fresh air intake path, when the valve is in the closed position.

Correction (1999-2007 Classic/Old Style Models)
After following the published SI diagnostics and determining that the EVAP canister vent valve is the cause of the MIL light, replace the existing EVAP canister vent valve assembly with a new assembly. This new assembly is a sealed unit that is designed to be vented through a remote filter box. To ensure correct installation, follow the procedures below.

Part Number
19207762 (1999-2003 Model Year)
Solenoid Kit, EVAP Emission Canister Vent Valve

19207763 (2004-2009 Model Year)
Solenoid Kit, EVAP Emission Canister Vent Valve

 

Billy, u need 1 of those $22 units? Sounds like u verified on your PO446 that it's not anything else than a bad vent valve. While I didn't know "light will stay on til EVAP monitor runs again & the system passes the test, there are a bunch of parameters that have to be met for the EVAP monitor to run.
Every so often the light will go off for a day or two, until the monitor runs again and the system fails. Have the code cleared and see if it comes back."

I cleared code, & haven't checked, but I'm back to not being able to fill it. So my guess is code came back; it sure was nice to be able to fill just once w/. it workin at least at little better. Not 100%, but not how it did me yesterday.

williebones, vent solenoid if I was given correct info was $22. But Billy said that's the older solenoid, not the updated 1. He said the newer 1 he hasn't found for under $110. Ouch!

I'll find out today, cause I gotta get a part or 2 from dealer. The $22 part he had in stock, IIRC. But if it's not the improved version, I might pass. I don't ever wanna deal w/. this crap again.

I've tried different pumps at the same station, a.w.a. different stations, but always Sunoco.

I didn't know there was all those codes for the same issue: refueling headaches due to shutoff. I just wanna have the issue end, but if it's not that part, I'd hate to spend $110 or whatever, on a part I don't need.

 

Thanks for posting this.

Please see my comment to Joseph (just above). So, for my '04, I need #19207763, but do I need the remote filter box too? Or does that p/n u mentioned include that?

Any chance u have that p/n too?

 

Part # 19207763 includes the remote filter box. Our regional field engineer was having us relocate the filter box to under the hood near the brake booster to prevent water and debris from getting in the evap system. If you have refueling issues, you may also want to check the evap cannister for excessive dust which would cause a P0446 to set if it were restricted enough. When you take down the cannister, see if dust will come out the 2 large fittings. If it does, you may want to replace it too. FYI, dealer cost on part # 19207763 is $76.90.

Joseph

 

fastnblu did you ever but the part to fix this? I cleared my code after I first posted and it came back on today

 

finally got around to replacing the evap vent solenoid today, GM part number 25932571, ACDelco part number is 214-2149. This is the old style part which is $28 at the dealership not the new style part which is $120. Install was pretty easy, I have not cleared my code I'm going to wait and see if it will clear itself in a few days.

old part:



new part beside old part:


new part installed:



If anyone knows the part number to the white fitting I need the locking clip for it, i broke mine in half taking it out but was able to use the broken pieces to lock it back in place for now.

 

anyone know the part number the the white fitting in this picture? it connects to the EVAP canister

 

I just got done doing this repair using the part number 25932571 on my 2005 Chevrolet Silverado Crew Cab. It is the same exact part that came original on my truck. The cause of my "tighten gas cap" code was overfilling the case tank.

Before I did the repair, I bought a new gas cap. I reset the codes by removing the negative battery cable for about 30 minutes. I put the cable back on, but after a short drive the "check engine light" came back on and my display said to "tighten my gas cap".

I pulled the negative ground off before I did the repair to so I would not have to wait for the codes to reset.

For this repair, you will need part number 25932571, a razor blade to cut the original hose off the reused fitting, 2 ft of 1/2 inch gasoline hose (needed only about a foot, but o'riellys sells it by the foot, so I bought the extra length just in case, less than $2.50), and two hose clamps. One of the easiest repairs I have done. Hardest part was removing the canister and the pipe fitting and that wasn't difficult.

After the repair, my "check engine light" was off.

Dave

 

i had the same code come up, went over to my buddy at the GM dealer, got a AC delco one, I got two items in the box, one is the solenoid and the other is like a box with a foam filter in it, were does that go?