Ever since I got my Fit last year I have been getting the stink of the catalytic converter getting raw gas, so I guess, being nothing more than a 'shade-tree mechanic' occasionally when pulling a hill or when I needed to give extra gas... in other words: under a load. Well, last weekend I put on the Megan cat back and the stink went away! And the car is more powerful (lol) since the sound from the back sounds more powerful... Why would the stink go away? AND the sound from the filter box (I put in the K&N drop in OEM replacement) is no longer. Was the car being choked or what??