Codes P0 420 and P0 430

[dna9656]

I just got this truck, the day after I bought it (137K miles on it) the CEL came on, it shows codes  P0 420 and P0 430, is this an indicator of bad Oh-2 sensors or does this show the Oh-2 sensors are alive and well and I have bad cats?  What is the forum's exp. please? I have read it could be either or both, that I should diagnose the cause and fix it before buying parts. I seem to remember a Oh 2 sensor could be tested with a butane torch, you put the sensor in a vice put some heat on the Oh 2 sensor and test it for voltage, could it be that simple? I think the Volts were 1 to 1.5? Can anyone shed some light on that?

[CamGTP]

Those codes are usually always just bad cats or from cats that aren't OEM.

 

I'd stick your head under there and see what they look like, if they look brand new, it's likely not an OEM y-pipe anymore. Maybe a take a picture and put it up on here, it's pretty easy to tell an aftermarket cat from an OEM cat.

 

There are tricks to keep the check engine light off with aftermarket cats. Either through the non fouler trick or custom tuning.

[silveradosid]

can your scanner monitor the maf and o2 sensors

[silveradosid]

you could try this