Troublecodes

I have a trouble code poping up on my 96 integra saying incorrect purge flow. I have replaced my canister, solenoid, purge valve, all of the hoses that connect them all to the intake manifold. I have also heard that it could be my gas cap so I replaced that. I don't know what it would be that could be throwing off this code. The trouble code is P0441. I have gone to troublecodes.net/acura and that just told me what it was not what it could be that is wrong with my car. Any information that could help me would be great. I have been trying to figure this code out for awhile.