I know this subject has been beat to death. I have a 2005 crew cab 1500
silverado. I have replaced the evap solenoid and valve. Put smoke into the system and seen nothing. I did not have this problem until the truck was driven over a large pot hole. Is there a chance that something was jarred loose on the fuel pump? I'm about to remove the bed to get a good look at the pump and hoses. Been having this problem for over a year now.

 

did you check the purge solenoid also while you were at it.if not maybe your purge valve is bad and causing your issue.

 

what code? and which solenoid did you replace?

 

If there isn't any smoke that you see when you smoke test it, getting a better look at the hoses might not be necessary lol. DTC's would be helpful though if you could post them.