2003 Gmc Sierra Dtc P0446

[kotruckin]

I have a 2003 GMC Sierra 4.8L 1500 single cab. My SES light came on about a week ago so I went to advance auto parts and pulled the code p0446. Do I replace the vent valve or the purge solenoid. The new solenoid kit is like $140 but there is also a part for around $25. I would like to buy the cheaper one if it will fix the problem. Also, where are these parts located on the truck and will I have to drop my gas tank to access and remove the parts?

[kotruckin]

So here is the update where I am at now. I found the elusive filter. It is the square kind and it was in a tight space on top of the gas tank. I could actually see it when I looked down between the bed and the cab. After wrestling with it on my back in the street for about 30 minutes I managed to squeeze it past the frame so that i could blow it out with the compressor. It was a little dirty but nothing came out of it or the hose when I blew it out. I'm going to replace it with a new one tomorrow hopefully and see if that does the job.

[kotruckin]

So the parts stores in my town do not cary the solenoid kit that I need to replace the old one. I am ordering it and having it shipped so it may be another week before I actually get this done and am able to get my emissions tested. On the upside I did find the parts for just over $100 which is cheaper than the auto parts stores advertise online.

[kotruckin]

Finally got the parts in the mail from ACdirect for around $90. I ordered AC Delco part number 214-2081. This is the evap vent valve solenoid kit. Most places had it for $100 and up online. It comes with the the solenoid ( the round cylinder thing with a bracket on it), the tubing to go from the solenoid to the charcoal canister, and the little vent valve box. The only thing it does not come with is the 5/8" heater hose and clamps to relocate and connect the vent valve box to the solenoid. The hose and clamps cost around 7-8 bucks at your local auto parts store depending where you live. On the 2003 GMC Sierra 4.8L the part that set off the code looks like this...

 

This assembly is located in between the bed and the cab and the tube runs over the top of the gas tank.

The replacement part (AC Delco #214-2081) looks a bit different but is supposed to fix the problem from happening again.

If you search for evap vent valve solenoid on this forum you will find a lot of information on this topic and I just wanted to add some more pictures and the way I hooked everything up. I don't see the point in hassling with the transmission and using 5 ft of heater hose to relocate the vent valve box. I just zip tied it to the gas fill hose and it is out of the way and not near any heat sources. Thanks to everyone who has posted their information it really helped me out.

[kotruckin]

Here is the square vent valve box and bracket close up.

[kotruckin]

This is the new solenoid bolted into the same bolt that the old one came off of. It is a different bracket that repositions the solenoid on the outside of the frame instead of inside where there is no room.

[kotruckin]

In this picture you can see the small black vent valve box in the right of the picture zip tied to the gas fill hose.