Hyundai Forums banner
1 - 8 of 8 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter · #1 ·
Got a CEL today driving on frozen snowy roads.
actron CP9145 scanner showed P0431 two times.
Searched this forum and I understand it's either Bank 2 downstream sensor O2 sensor or cat con itself.

This is what is puzzling. In I/M readiness mode it checks bunch of stuff but it say Oxygen Sensor Mon OK and also Oxygen Sensor Htr ok and Catalyst Mon Ok and Htd Catalyst Mon ok.

I really don't know what to do at this point.
Oh and I assume that Bank 2 is the closest to the firewall right?
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #2 ·
More data:
02S11(V) .08 to .78
02S12 .46 to .5

02S21 .16 to .84
02S22 .18 to .58

I understand (from what I read) that the downstream O2 sensor should have a lower reading than the upstream. From these 4 readings above which two do I compare?

If I do have to buy a cat con or O2 sensor, are these Dealer items only?
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #4 ·
Thank you santa06. Very helpful link. I now figured out that it is the cat nearest the radiator that is bank 2. Rock auto describes it as follows: " Exact-Fit Catalytic Converter - Pre converter". About $175. The weird thing is that the Hyundai shop manual shows the flange as a 4 bolt on the one side. Rock Auto shows it as a 5 flange.
 

·
Registered
Joined
·
4,851 Posts
My guess is your cat is fine. You should drop the exhaust pipe from the cat end and look in there. If the catalyst is still intact, then it's fine. I too get the dreaded p0431 with my Kia Sedona, but I assure you it runs fine and gets excellent mileage, so I learn to like the pretty lights on my dash. No emissions inspections in Florida you see.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #6 ·
I'm looking at Rock Auto for O2 sensor. They refer to downstream Right or Left. Bank 2 (closest to radiator) is Left or is it Right? Also is there a sight to look up the OEM Hyundai part numbers?
 

·
Registered
Joined
·
390 Posts
1 - 8 of 8 Posts
Top