2014~2018 Does fuel injector cleaner work?

[ZDA3]

It seems the code P0421 disappeared after I had recently used a fuel injector cleaner. One that you pour in the gas tank when filling up.

 

[concept]

P0421 MAZDA Possible Causes
Warm Up Three Way Catalytic converter deterioration or malfunction
Exhaust system leaks
Loose front or rear HO2Ss Faulty front heater
O2 sensor
O2 sensors harness is open or shorted
O2 sensors poor electrical connection

 

[Bjorg]

Based on my experience, yes, it works.