Removed the air box cover and noticed that the K&N air filter was not pushed all the way into the intake tube. I pushed on filter and the fit was not a very tight, I'd consider it somewhat loose.

Has anyone encountered this and if so, how did you correct it? I am considering trying the K&N Air Filter Sealing Grease.

 

This part of the S2000 is a little different than other Hondas I've owned / encountered. Most of them had a long spring that would circulate around the rubber intake tube where the filter goes in. This ensures a snug fit at this junction. The S2000 intake tube has a provision for this (the narrow channel right where the filter meets the tube) but on mine, there is no spring.

A simple solution for you? Just take a hose clamp (make sure you get one that can go over 3") and simply install it around the neck of the filter in the intake tube arm. Don't make it too tight, it doesn't take much. I've noticed that these clamps can loosen over time, so just check it like at every oil check.