Check Engine Light Trouble Code P0430 Catalytic Converter Low Efficiency

Here we have a second-generation Cadillac CTS with a check engine light and a code, P0430. The description of this code is catalyst system inefficiency bank 2. Let's see what's wrong with it.

The catalyst system has to do with the catalytic converters right here. So you have bank 1 catalytic converter and bank 2 catalytic converter. When you're running your engine, the exhaust comes out of the engine and there's some unburned fuel and air. It goes into the catalytic converter and it burns up the rest of that fuel, and then it comes out here, and then goes out to the tailpipe. And how the computer knows that the system is working is with the two O2 sensors. You have an O2 sensor in the front and an O2 sensor in the back. And the difference of the O2 sensor readings is gonna be how efficient the catalytic converter is working.

Before we lower the vehicle and check the status of the O2 sensors while the vehicle is running, some things you should check out, make sure there's no leaks in the area of the second O2 sensor. If you had a leak right here, you're gonna wanna fix that before determining whether you need a catalytic converter or even any leaks further back. Make sure there's no leaks coming from the converter or even before the converter. Visually look at it, make sure it looks okay, it looks similar to the other one if there's two, and make sure it's not severely discolored.

You wanna check the wiring on the O2 sensor, take a look, make sure it hasn't rubbed on anything and there's bare wires. This one looks okay. If there is a situation, you wanna take care of that first. Also, when you're looking at the converter, if you see any dents in the converter, that's not good. And if you take a hammer, like a rubber mallet, and you hear major things rattling inside there, then it's gonna have to be replaced as well.

With the RPMs up, you can watch the front and the rear O2 sensor, and it is following the front a little bit. This converter is probably not completely not doing anything, but it's definitely not as healthy as the other side. If you look at this, this is kinda how it should look. This is the passenger side, and this is the driver's side, which the driver's side is the one that's giving us the code.

It looks like we need a new catalytic converter, at least on the driver's side. Now, some things you wanna think about before you just replace the catalytic converter, if the engine is not running properly if it's burning engine oil or coolant's getting into the exhaust, that's gonna just cause the new converter to go bad again. If you have any type of misfire, you wanna fix that, or if your spark plugs are old, you wanna replace the plugs as well. Catalytic converters are expensive, so make sure everything's running up to par. If you enjoyed this video or it helped you out, make sure you subscribe to our channel, ring that bell, turn on all notifications so you don't miss any of our videos.