× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network
Re: Possibly stupid question...non-monitored downstream cats
Posted to Emissions Forum on 12/14/2018 1 Reply

[...trimmed text...]

That's not accurate. Rear O2 sensors are used for fuel trim as well as self-testing. Toyota used them for fuel trim from the mid-80s, well before OBDII and the requirement to monitor the catalyst syst... Login to read more.

1 Replies Received (View Replies)