P0446 evap vent diagnostic 00 Sierra 5.3L V8

[tejay]

My 2000 Sierra 5.3L v8 has had a P0446 error code for some time. I had the evap vent retrofit kiet installed with no change in symptoms. I can go for 2 days, 2 weeks or 2 months before the Service endine soon light comes on again. Sometimes I think it' the weather or maybe the load I'm hauling, or possibly the ethanol in the gas, but this problem just will not seem to go away. Any suggestions?

[kstruckcountry]

guys ,,,always always always replace the canister and vent solenoid together with evap vent code ,,,,relocate the filter to under hood (under m/cyl or behind battery) if ya get the 2 pc vent solenoid with 5/8 heater hose

 

ps ,the relocate that GM did on top of the tranny is NOT a good place ,,i used to relocate them to the engine bay as well lol

Not sure why they wanted to put it on the tranny... stuck mine behind the fuse box and it rides there fine.

[gmtech4]

Not sure why they wanted to put it on the tranny... stuck mine behind the fuse box and it rides there fine.

Exactly !! We had no problem selling the relocate , not a bunch of extra time to run some heater hose

[kstruckcountry]

You need to replace the evap canister as well. Same thing happened on my 2006. What happens is dust gets past the POS filter in the original evap vent and plugs up the main canister.

[gmtech4]

guys ,,,always always always replace the canister and vent solenoid together with evap vent code ,,,,relocate the filter to under hood (under m/cyl or behind battery) if ya get the 2 pc vent solenoid with 5/8 heater hose

 

ps ,the relocate that GM did on top of the tranny is NOT a good place ,,i used to relocate them to the engine bay as well lol