Fiesta st rich fuel smell

[hockeyman]

so I've been chasing this problem and have no clue if this is a catalytic converter thing or a actual fuel trim problem or a o2 sensor problem. As I had installed a catted 300 cell whoosh downpipe, i got a P0420 code which was expected from the catt. So i purchased a whoosh defaulter to combat the code but at this point as i let the car heat up and get to operational temps. I smell a rich fuel coming from the exhaust not raw fuel but unburnt fuel, and i got a tune from dizzy and a remap from him and he said the afr trims were perfect. So im not sure if the defouloer is causing a improper afr trim due to the spacer or is this just a high flow catt problem and would adding another catt combat some of the smell.

thanks for the help guys

 

[XR650R]

https://www.google.com/search?q=P0420&rlz=1C1GCEA_enUS1144US1144&sourceid=chrome&ie=UTF-8

 

[Sam4]

I believe our defouler, and catted, but non-oem converter allow some stank through. I get to about the same light every morning, come to a stop and ..*whew*. There are lots of random comments regarding downpipes on this forum, with smell being a common thread. So, yeah, another deal-with-it situation.

 

[TyphoonFiST]

I run No-cat...rear defouler and no complaints on smell. Just gotta make sure the gaskets are all still ok in the exhaust system so there is no leaks.