Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - What is a "rear" or "secondary" catalytic converter for?

California98Civic · 06-06-2018, 12:51 PM

Hyundai has been fitting "secondary" or "rear" catalytic converters on cars for at least a decade. Probably other automakers do too. Hyundai's rear CAT has no O2 sensors to monitor its function and is further down the exhaust line.

Here is an eBay replacement for a Santa Fe:
https://www.ebay.com/i/253610843152?chn=ps

Here is a salvage from an Equus:
https://www.ebay.com/i/2011-2012-201...664?rmvSB=true

The featured picture I attached is of a cheap aftermarket knock off replacement from autoparts direct because ebay won't left me save the photos of its cheap aftermarket parts to my computer. Hahaha.

Is this thing for NOX or something? Anyone know?

THANKS FOR CITATIONS TO RELIABLE SOURCES!

06-06-2018, 12:51 PM	#1 (permalink)
California98Civic Cyborg ECU Join Date: Mar 2011 Location: Coastal Southern California Posts: 6,299 Black and Green - '98 Honda Civic DX Coupe Team Honda 90 day: 66.42 mpg (US) Black and Red - '00 Nashbar Custom built eBike 90 day: 3671.43 mpg (US) Thanks: 2,373 Thanked 2,172 Times in 1,469 Posts	What is a "rear" or "secondary" catalytic converter for? Hyundai has been fitting "secondary" or "rear" catalytic converters on cars for at least a decade. Probably other automakers do too. Hyundai's rear CAT has no O2 sensors to monitor its function and is further down the exhaust line. Here is an eBay replacement for a Santa Fe: https://www.ebay.com/i/253610843152?chn=ps Here is a salvage from an Equus: https://www.ebay.com/i/2011-2012-201...664?rmvSB=true The featured picture I attached is of a cheap aftermarket knock off replacement from autoparts direct because ebay won't left me save the photos of its cheap aftermarket parts to my computer. Hahaha. Is this thing for NOX or something? Anyone know? THANKS FOR CITATIONS TO RELIABLE SOURCES! Attached Thumbnails __________________ See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread. Last edited by California98Civic; 06-06-2018 at 08:22 PM..