Nissan Repair: Engine Idle, infinity fx35, nippondenso

Question
I have a 2009 infinity FX35. At 650rpm,and engine at normal operating temp.,and in drive, the engine idle is ruff. You can feel vibration thru the steering wheel, and seat. Can you tell me What might cause this and how to fix it. I have been to the dealer, and says no computer code shows anything wrong.Can you help with this problem? Thanks

Answer
Bill,

This is under warranty.  I would take it to Infiniti and have them look at two things.  The first is a defective injector or two and next would be a plug misfiring.  But, it is probably an injector.  Renault bought Nissan and now there are European injectors getting into the parts supply and they are not as robust, in my opinion, as the Nippondenso injectors.  Infiniti has a Consult II or Consult III Scan Tool to diagnose the problem.