Check engine light due to catalytic converter

How is removing the o2 sensor going to turn the check engine light off?Also what is the exact code numbers not code descriptions setting P0420?Also gutting the cats are illegal.

Thank you for reply. My car was showing checkengine light after I removed the honeycomb in the cats ,so I took my car to a service centre ,let me tell you they did scan the computer and told me that its due to the catalytic converter as their device was showing, I have seen some videos on web solving thus issue by putting sparkplugs on sensor making it far away from banks ,so I just want to ask that if I just unplug the sensor and then resetting the light ,so will it affect anything else?

If you unhook the o2 sensor its still going to keep the check light on and set more codes.Also the o2 sensor inputs help the engines computer regulate if the engine is getting too much fuel or too little so the computer will adjust for that.I wouldn't unhook the o2 sensors. Why did you gut the cats were they plugged? Which state do you live in?Also which cats are they?

actually i had some leakage in one of the banks so i took my car to a service center, some mechanic suggested me to remove the honeycombs and said that it will enhance your engine performance, as at that time i was unaware of it , but after that check engine light is continuously on and im pretty much aware that these cats are very expensive.please let me know if there's any other solution? I live in Saudi Arabia and i don't think this country has any type of law regarding these cats by now.

these are pretty much similar

So is the car a federal emissions car not a California car?Also which engine do you have?These are the cat's that come right off the exhaust manifolds?Unfornately the computer is set up to run with cats so it looks for the difference in o2 sensor readings from your upstream o2 sensor to your downstream o2 sensor. If it doesn't see the readings it wants it sets the cat low efficiencie.

its a 3.6L V6 engine. any solution? :(

Are you sure its a 2009 lumina?Iam having trouble finding that year with that model

Yeah it's a 2009 lumina.this brand name is only in GCC countries where as in other countries it is known as "Pontiac G8" or "Holden commodore VE"

The only way I know of turning the light off is put some new cats back on.

What if I put spark plugs non foulers to keep it at a distance from cats.I have seen many videos on web regarding this

You can try It i have never heard of anyone doing that or trying that and it working.Let me know how it works.Not sure if the o2 sensors are going to work correctly to regulate fuel.