I posted this several months ago but for all new "Z" owners.. Remove your air filter every so often and check for leaves and other junk that may have been sucked into the air box. I was surprised the first time I did this (after 6000 miles) when I found about a dozen leaves plus other assorted pieces of junk (paper etc) had been sucked into the area in front of the filter.. Very easy to check.. Just pop the 2 clips and lift the filter out.. Get enough stuff in there and your performance will drop sharply..

Steve (k2we) Dobbs Ferry, NY 10,503 miles since Sept 17th....

 

I installed a K/N filter last week and I too was amazed to see all the junk that was in there...I am checking it everytime I wash the car now...