The "check gas cap" code popped up again driving home from work. So apparently it didn't just need to be pushed in properly.

How likely is it that being loose has damaged the big unit thing?

 

Not very

 

You need to charge the system and find the leak.

 

Perhaps it’s the wrong cap, some after market gas caps just don’t work, I have a Stant and I think a Dorman , both failed.

 

Find a shop that is confident in doing a “smoke test.” I’ve been chasing a a “small” evap leak for over a year. Apparently too small for a smoke test to detect. Wish it would turn into a large leak.

 

well its from the chevy dealership lol I bought a new one.

The local shop wanted $175. I think I will just but a smoke tester and do it myself.

One video I looked up started at the front unit connector. Will this be okay on the SS even system? Is there a PSI I should stay under?

Would blowing vape clouds into it work?

Anyone done a smoke test on evap lines themselves?

 

If they have a good machine it will have a tank of nitrogen and you charge it with that and use a spray to find the leak.
If you can charge it yourself with about 4 psi of air and do the same thing. Nitrogen finds smaller leaks but air finds 95% of small leaks. Many times when smoke won't find it it may be the canister is degrading.

 

Air is 78% nitrogen so you wouldn’t notice much difference

 

It don't work like that because the larger molecule will always block the smaller hole. At any rate the difference between nitrogen and oxygen is not much.

 

Can I use a Dewalt jobsite blower, duct tape and a cigar?