Catalytic Codes

[06S197GT]

No cats, it's an offroad H. My understanding was that the tune would turn those o2's off, maybe i'm mistaken.

I'll check the pipe but can't imagine how a wire would get damaged, as i checked it all post install.

If the tune doesn't have the rear o2's turned off then it's a no brainer. No cats + working o2's = fail = CEL.

If they are turned "off" per the tune, would a damaged o2 sensor or wire still cause the CEL?

If all else fails you can fab up some non-fouler plugs and see if those help. Its hard to tell if the rear O2s are on or off with the SCT but I will tell you that before I had my car dyno tuned by Manny I had a Brenspeed email tune that claimed they were off but all their tune did was cause a non-ready status; no CEL but the code was still there. I'm not saying that that is what is going on in your situation but its a possibility.

[clevelandkid]

I would call SCT to check with them... I think if the car had the 2 codes and they were not cleared before the tune was loaded, it would allow the CEL to come on.

I run the canned tune on mine, and did not disable the rear O2s when I loaded it. It took several months, but I eventually got the same codes you did. I cleared the codes, then reloaded the canned tune, but also added to turn the rear 02s off. I haven't had the CEL since.

[Old Man]

Try clearing the code wth the SCT, remove the key from the ignition. Disconnect the negative battery terminal for a couple of minutes then reconnect the terminal and start the car. CEL should be off.

[turbos66coupe]

p0420,430 are cat effeciency code. this code(s) will not set due to a bad o2 sensor. if it were a bad sesor ie reading excessivly high or low voltage or none at all it would set a circuit malfunction code. same if it was a o2 heater circuit problem it would be a different code with a diff descripiton. and p0420 sets when the rear o2 reading is following the up stream o2's. the up streams should switch between .2v and .8v with a set number of switches above and below .45v every few seconds while the rear (cat monitor ) should stay steady. if you have a p0420 there is problem with your tune.