2013 Genesiis 3.8 sedan Code P0420/P0430

[AMANDO]

Will changing both O2 downstream O2 sensors correct CEL. How long does it take to drive car for the computer to reset to new Walker O2 sensors?

 

[Sal Collaziano]

Will changing both O2 downstream O2 sensors correct CEL. How long does it take to drive car for the computer to reset to new Walker O2 sensors?

Welcome. Moving this to the first generation Genesis Sedan section...

 

[joegr]

Will changing both O2 downstream O2 sensors correct CEL. How long does it take to drive car for the computer to reset to new Walker O2 sensors?

I'm not sure why everyone is so quick to "shoot the messenger." Those sensors are trying to tell you that something is wrong, such as your catalytic converters may be worn out or damaged, or it may be that the engine's emissions are way off. It's possible that the O2 monitors are actually both bad at the same time, but it is not at all likely. I would diagnose the problem, instead of throwing parts at it.

 

[Qship]

When my O2 sensor went, it would intermittently throw a code here and there (I don't think it was P0420 or P0430). My last 2 cars I had P0420 codes. on one car, it was the pre-cat (exhaust manifold with built in heated cat). On the other car, it was the cat itself that was plugged. Best thing I can advise is what @joegr said. Get it properly looked at. If the cat is plugged for example, you're just doing more damage to seals and other parts by driving it around thinking that it's the O2 sensors.

 

[user0209]

Hello @Qship and @joegr and anyone,

I don't mean to hi jack this thread but since you two mentioned the Catalyst, do you know why the "Catalyst" is not ready, (shows red X in OBD2) when the car first runs but after it has run extensively, the Catalyst shows ready / green check?

Does running the car "heal" the catalyst?

 

[Qship]

Hello @Qship and @joegr and anyone,

I don't mean to hi jack this thread but since you two mentioned the Catalyst, do you know why the "Catalyst" is not ready, (shows red X in OBD2) when the car first runs but after it has run extensively, the Catalyst shows ready / green check?

Does running the car "heal" the catalyst?

Yes. it won't be in "ready" status until it's reached "catalyst" temperature to burn away carbons etc. I think it's around 800 degrees Fahrenheit (400 something degrees Celsius). and NO, it doesn't "heal" anything. The Catalytic converter just doesn't work until it's heated up.

 

[joegr]

.... Never mind, answered above