p0441 incorrect purge flow.

checked vehicle found friend replaced purge, some vacuum lines. code returned. connected vacuum pump to one end of purge and actuated ok. vacuum drops. checked vaccum switch, opens and closes. checked engine vaccum at manifold 20 in hg. checked proper installation of vaccum hoses and lines ok. Is there any tsbs possible a pcm flash. Does this system use a vsv (vaccum switching valve). canister lines look ok. Did not smoke test system yet, need to drive vehicle to work. Any suggestions

Gas cap is bad? Not sure cause I'm at home so I can't check any info.Just thinking that the tank might be pressuized.

but wouldn't that throw a p0455, 0442 or 0456 a emission leak instead of a complete failure??

checked vehicle found friend replaced purge, some vacuum lines. code returned. connected vacuum pump to one end of purge and actuated ok. vacuum drops. checked vaccum switch, opens and closes. checked engine vaccum at manifold 20 in hg. checked proper installation of vaccum hoses and lines ok. Is there any tsbs possible a pcm flash. Does this system use a vsv (vaccum switching valve). canister lines look ok. Did not smoke test system yet, need to drive vehicle to work. Any suggestions
Not an issue with this code, but get used to posting year and engine please. NO vsv, the pcm actuates the purge valve. Smoke test is next, if you can it it on a full bidirectional scanner some year cars will allow you to command and confirm the purge solenoid operation.

96 5.7 350. I connected a vacuum pump to one end of purge and actuated with scanner and found vacuum drops, connected scanner to one end or vacuum switch and pulled vaccum switch stauts changes from open to close. Smoke test is probably my best bet, but I need to take this thing to work,