I have the same problem with my 2008 Silverado. I replaced the purge solenoid and gas cap and the vacuume canister and still get the code po496 after about 4 or 5 drives. Also hard to start on fillups. Will have to check that vacuume on the back port even thou I replaced it ! Wanted to know, did u have the code po496 when u had your problem thanks ! Carl

 

yes, if the purge solenoid is not sealing the system it will set evap purge during a non purge condition dtc p0496. do the same check that was recommended. no air should pass the purge valve when the purge valve is off.

 

Thanks for your quick response and answer ! Appreciate any and all help. CARL T

 

Yep, there is a vacuum at idle ! Guess Iam not the only one that has to replace a new part . The ! Carl T. Will replace IN A couple of weeks and let you know the results.

 

A big thanks ! Can't believe the poor quality of new parts these days, now I am sounding like my old Man from many many years ago �� Just like the guy above me in the previous thread just replaced the New purge valve with another New New purge valve and all is solved ! Thanks for the help seriously ! Would of never thought to replace the new part I just put on. For anyone's info, the new part that failed was AC Delco and the one that worked was BH. Thanks and have a great week ! Carl T. Cleveland Ohio

 

faulty new parts can cause headaches for even seasoned professionals.