I had a code po446 on nissan pathfinder 97. Code back no ser. light po446pd

Thank you for your answer. I have a data analyzer that I can turn off the service engine light and reset the codes but after about 80 miles the code with the pd comes back. Is it difficult to change the control module?

Ok, That means the fault has not been corrected. You will need further diagnostics to establish the cause of the code. The engine control module may be the issue, but there is no way to tell without diagnosis. Same with the purge valve. If low flow is detected, it doesn't mean the purge valve has failed, it means that is what was detected. Could be a host of issues, so it needs diagnosis.