P0440 And Evap Vent Valve

schnid21 · March 22, 2009

Hoping someone can help me troubleshoot this problem.

I have been getting this code (P0440) off and on for the last month and my truck is coming due for an emission test so I need to get it fixed.

I have done quite a few searches on here and just wanted to make sure of a couple things before I start replacing parts.

My first step was to replace the fuel cap (previous owner put a lockable cap on.) I purchased a new cap from GM and this did not correct the issue.

Second step was to check the solenoid on the engine. I removed the solenoid. Looks clean and doesn't look like it has any problems. I took a 12V battery and checked to make sure the solenoid works. With 0volts I was not able to blow through the solenoid. Apply 12V, I heard a click and the valve opened (air went through). Based on this I assume the solendoid is okay. Next step was I looked at all of the hoses/tubing for signs of wear and cracks. I can't find anything but that does not mean there isn't any.

My next plan was to test the EVAP Vent Solenoid by the gas tank. I found the solenoid and started trying to remove it. Unfortunately its pretty cold here and after about an hour of trying to remove the hose from it, I gave in and decided to try another day. While working on this solenoid I removed the large hose from the charcoal canister and decided to blow into it. The air went straight through, no restriction. So my question here is how is the Solenoid mounted by the fuel tank supposed to work? Should it be closed with 0V (key off) or open with 0 Volts?

Any help with this would be appreciated.

Thanks

Jason

bigredmariner · March 22, 2009

Jason it's a normally open solenoid and will only close when the system performs the check, or due to pressure in the tank. The vent solenoid failure is pretty common on these trucks and will most likely need to be replaced.

98 Z71 SLT · March 22, 2009

Agreed. There is an updated vent solenoid kit available from GM...check with your local GM Parts Department.

bigredmariner · March 22, 2009

BTW do a search and you should find a nice step by step write up that one of the members has posted, the write up is good I just used it last weekend to repair the same issue on my 06.

superjim · March 23, 2009

Check your warranty...

The emissions warranty may still cover you.

It is a lot longer than the regular truck waranty.

schnid21 · March 23, 2009

So did a little digging at dealership today.

They want $342.00 for the vent solenoid. I gave him my VIN# and thats what he came up with. Thats quite a bit in my opinion to just throw at the vehicle when radomly replacing parts. I don't have a problem replacing it if I need to but I want to make sure thats the problem before I do.

My other option is a smoke test I guess, cost about $100.

I also asked about emissions warranty and its no longer covered. Only the PCM and cat are covered under the 8 year warranty.

Any other ways of troubleshooting this before throwing money at it. Or maybe someone knows a different part number that I should call and ask about.

Jason

bigredmariner · March 23, 2009

Jason, are you going to try and do the repair yourself? For right at $100 you can order the solenoid and replace it yourself. Have you done a search and located the write up for replacing the solenoid? It's in this forum and is nicely done by one of the members. I ordered the solenoid from GM Parts Direct and it only cost me $76.13, spend a few buck on the hose and clamps and you're done. Try this number and see if it fits your truck, AC-Delco # 214-2082,also listed as GM part number 19152349.

You can spend the $100 bucks on some smoke, or you can spend the $100 bucks on some parts. Just my opinion.

schnid21 · March 23, 2009

Hey

Thanks for the tips, the only thing is from what I can tell that TSB does not apply to my truck. (http://www.gm-trucks.com/forums/index.php?showtopic=82504&hl=Vent+Solenoid) I assume your talking about the PDF that is in this link. It applies to 2003 and newer trucks according to the title.

When I called GM they ran my VIN and came back with the $342.00 for the solenoid which is pretty steep (guy on the phone even said thats the most expensive one he has seen). I searched around on GM Parts Direct and was unable to find the solenoid for my truck.

I am definitely all for doing the repair on my own, personally I hate other ppl working on my vehicles unless I can't help it. If everyone thinks this solenoid would work on my truck I would give it a shot. But if I buy it and it don't work, then I am out another 100 bucks because electrical parts are non returnable.

Thanks for any input everyone has.

Jason

bigredmariner · March 24, 2009

Jason, sorry that didn't help you maybe someone else will chime in with some better info.

schnid21 · March 24, 2009

Thanks anyway.

Not sure what the chances are of it working. But I have thought about possibly buying the part number you mentioned and adapting it to my truck. Maybe someone on here could post as to whether or not thats possible. It would be easy enough to create a jumper harness to relocate the solenoid. Mounting brackets are pretty easy to make and just running some hose is also pretty easy.

Any opinions on whether giving this a shot is worth it or not would be appreciated.

Does anyone know why the solenoid for a 2002 GMC Z71 is different than the 2003 and newer versions?

Thanks

Jason

MikeInCtown · March 24, 2009

Check the RockAuto website for the part. Along with the A/C Delco listing is also a listing of part numbers that this replaces. They also have info on what years and vehicles the parts fits.