Hi all,

My mdx flex pipe is deteriorated and has two big patches where wire mesh is gone and surrounding area has black soot. since this pipe is after first and second cat I don’t see any sensors on this pipe nor on the third rear cat which connects at the end of this Y/flex/down pipe. what I see third cat is not connected to ecu via sensors.

I want to know besides carbon monoxide hazard does this has any impact on car/engine performance? Car has no MIL light but I have degraded engine performance and loud engine hum.

 

that is called the J-pipe and it shouldn't be too much of an issue with CEL. Yes for carbon monoxide so it's best to have it repaired if hauling family.

Buy a used one or go aftermarket. RV6 makes one that deletes the 3rd cat.