Why does the engine need both pre and post cat O2 sensors? AFAIK the pre ones talk to the ecu and help keep the air/fuel ratio in check, what are the after cat ones for then?
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Why does the engine need both pre and post cat O2 sensors? AFAIK the pre ones talk to the ecu and help keep the air/fuel ratio in check, what are the after cat ones for then?
Sent from my D5803 using Tapatalk