What is the most probable cause for a P0455 code on a 2004 Infiniti G35X? on 2004 Infiniti G35

The car was scanned and a P0455 code was recorded. My understanding is that it's an emmissions problem, but where?

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1 answer
now, you need to repair your car by the following,
http://www.obd-codes.com/p0455
hope help.