[Dewey]

hello

i have a 2016 cx-5 with a p0421.

i searched the forum but minimal found on the topic. has anyone have this code before? im leaning towards it being a clogged cat.
trying to avoid the dealership.

 

[C J]

Google agrees with you; "The P0421 code relates to the catalytic converter in your vehicle's exhaust system. It sets when the Powertrain Control Module (PCM) notices that the system is not operating as it should be during the engine's warm-up phase."