I'm guessing you pulled it off and couldn't blow threw it. Can be stuck open or closed.

Could be the other sensor by the gas tank or a bad evap canister under the tank.

I'm still guessing the selenoid is bad. Just replace it and the sensor by the tank and see what happens. Dollars says it goes away. A whole dollar.

 

a whole dollar? haha do you know the part number by the gas tank?

 

https://www.cobaltss.net/forums/how-...-valve-240295/

GM part numbers:
Vent Selenoid - 25932573 - $32
Purge Selenoid - 12597567 - $41

 

awesome dude thanks!!

 

so before i go buy these parts you think i should try swapping out the purge solenoid? cause i already bought it and you said it could be stuck open or closed right?

 

If money isn't a big deal then go ahead and swap. Dang thing is going to fail anyway.

After how many i have been through and seen on here, I would say 8 times out of 10 it's the manifold sensor before the vent valve by the tank. 496 is the same code matching almost every thread about Manifold purge valve failure.

 

Ive had allllllll three codes and tha solenoid was 100% tha problem

 

ok so i drove around for a little bit today then check the purge valve again and it was open and i could blow thru it! I swapped it with a brand new one and i think i am good to go! hopefully its just that (which Im sure it is) and not the other valves by the tank! thanks for the help

 

That's good to hear. For those wanting to keep their car for awhile should probably stock up on these bastards. 3 in 36 months is stupid.

 

yeeah i bought 4 just in case

 

so i just went out to run a few errands and i floored in in 2nd and a CEL flashed a few times and went away. what is that all about? ive never had it just flash. car feels fine

 

If car wasn't warm then you are having misfires. I have never had it happen on my car but shouldn't floor it till up to temp.

 

it was definitely warm