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P0446

smac76017

By smac76017
in Ask A GM Technician

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smac76017 New Member

smac76017

Posted
Posted

Hi I'm new to this and was hoping to get a lil help. I have a 1999 Silverado 5.3 Liter VIN letter T with 128500 miles and I just got a DTC P0446. I'm pretty sure it's either the EVAP vent valve solenoid, EVAP cannister or the Purge solenoid. I don't have all the diagnostic tools at my disposal to diagnose this problem or a lot of money at the moment for that matter. I do see that a lot of people on this forum attribute this to the EVAP vent solenoid and I can see mine clearly between the bed and cab. I do not wish to just throw parts at this problem but do want it to go away. I also do not wish to relocate as in Corporate Bulletin Number 02-06-04-037E. I've seen people on here also talk about this being due to topping off the tank which I have been doin forever and never had this DTC show up. I've heard that this part costs over a 100.00 bucks but have also heard that the same vent valve for 2006 Suburban, GM Part # 25932571 which is around 25.00 $ can be used, that is at least for 2004 Silverados and up. Anyways, is there anyone out there that could help this old shade tree mechanic with some diagnostic tips and or cleaning procedures so as to eliminate at the very least the purge valve before I just start throwing parts at this problem? Thanx.

grose67 Enthusiast

grose67

Posted
Posted

I aint saying this is reccomended by anyone cause it aint. I took the hoses off at the evap cannister and blew a very low pressure stream of air through the cannister. I put it back together and cleared the code. That was about a year ago and it hasnt come back since. I consider myself to be a barnyard mechanic hoping to someday move up to shadetree mechanic.

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