Besides the gas cap, does anybody have experience with any emissions issues with the Tahoe? I have an 07 with just over 50K miles that has a K&N air filter, driven in city conditions, so no real dusty dirty air. I checked the cap and it is tight, but the emissions light is staying on. I can take it down to Advanced Auto and see if they can read a code? Not sure if they can do that like they can when the check engine light is on.

you should get the code read so you can know which code you have, part stores can usually do it. there are several evap codes if thats what you get. one common cause for those vehicles though is the evap vent valve, ive had some good luck just taking it apart, cleaning and shooting the solenoid with wd40 and working it back and forth with a 12v battery on the bench

Took it to advanced auto, code is P0451. So ya It'* an emissions code.
They would not reset it to see if it comes back on.
Do you know where that valve is? I can probably do as you suggest or even
Just replace it. I would rather not go to the shop.

its by the fuel tank i think on that. ive tried just replacing it on my last car the original lasted like a year and a half, bought a new one from gm, and it lasted a year. wd40'ed it and never had it fail again for 5 or six years that i owned it.

Doing a little reading, it sounds like it is above the spare
tire, on a cross member. I can check, but not today. Do you know
if it will hurt driving it like this for a couple days?

it wont hurt anything

Well I actually got in the garage and did get it off. So did you
just spat WD 40 into the canister the solinoid is attaced to
because I don't see how that whole assembly would come apart.
Does a new one come with that piece of hose attached to it?

looked up the pic on napa, yours is a little different, they put that stupid heat shrink line on there looks like. but still you should be able to get the bigger part apart and there should be a filter you can blow out and then you should be able to shoot it in from that side

Well, I'm not sure it was suppose to come apart, but I did get it apart. I sprayed
some WD 40, worked the solinoid with the battery, put it back
but the light remains on. Wonder if I should just order a new one?

Where did you find the part on-line? Should I buy it
from the dealer you think?