Need help with the EVAP system!!!

[Steve Cole]

So I got a "service engine soon" light and it is a code PO446. According to the Autozone computer, it could be two things, I chose the easier part first, the solenoid on top of the engine. It didn't fix it. So that leaves the purge control valve. This lives on top of the frame rail between the cab and the bed on my 2002 5.3 Silverado. It is attached somehow to a metal bracket that is bolted to the frame. I can unbolt it but with the bracket attached, it won't come down far enough to get to the two wire plug or the hose for removal. The only thing I can think to do is remove the bed but I really don't want to do that.

Has anyone replaced this valve? If so, how did you do it?..I need some help!!
Thanks.

P.S., the gas cap is tight. I checked that first.

[1978chev]

Purge valve should be attached to the charcoal canister which should be held in with a couple bolts and then some hoses it's really not that complicated just get a flashlight and take your time and look at it real close. Should not have to remove bed at all

[95 S_Trucker]

Originally Posted by 1978chev

Purge valve should be attached to the charcoal canister which should be held in with a couple bolts and then some hoses it's really not that complicated just get a flashlight and take your time and look at it real close. Should not have to remove bed at all

The purge solenoid is mounted on the intake manifold. The vent solenoid is mounted above the frame rail at the back of the cab/front of the bed.

It is better to give no info than false info.



The vent solenoid can be a pain to get to. But I have changed them with out dropping the tank or raising the bed. You can get creative with with long picks or screwdrivers to unclip the solenoid from the mount. Then its just the hose and the wire connector.

There could be a leak anywhere in the evaporate system causing the light to be on. I smoke test them, but not everyone has access to a smoke machine. You can also excersize the solenoids using a bidirectional scan tool. The vent solenoid makes an audible sound.

[68C15]

So far every P0446 I've dealt with on these has been dust and or bugs plugging up the vent filter. The dust get past the foam filter and ruins the valve

IIRC GM has an updated vent valve with longer hose to draw fresh air from gas cap area and a cyclonic canister