Nissan Repair: Oil changes, infiniti fx35, long periods of time

Question
I own an Infiniti FX35, that is only driven on weekends.  There are times when it is not started for up to three weeks.  The car is 1 year old and only has 3700 miles on it.  What schedule should I use for oil changes since mileage is not a factor?  Also by having the car sit for so long am I doing damage to the engine/trans from Non-use?

Thank you.

Answer
E. Pinedo,

I would start the car and drive it around the block once a week for good measure.  I would change the oil every three months to keep the warranty up.  You could get away with changing it every six months but the warranty would be voided.  So, do the three month thing since it sits and the oil will get condensation in it and that could cause internal rust.  But, I would do the start it up and drive it around every week to get it to operating temperature.  Another thing you should do it keep the gas tank full as they love to rust inside when water condenses in there.  A full tank reduces the risk of rust in a car that sits for long periods of time.