Need to pass smog Cal '07 Malibu p0430 code

[Wolf359]

As others said, the cat is probably fried. However if you look up the code, it also mentions checking for an exhaust leak. That could also cause the code, if it's not that, then the cat is probably bad. Usually if the pre-cat O2 sensor is bad, you can fix it by replacing the sensor, but usually the post cat sensor doesn't go bad. You could get it diagnosed by checking the voltage levels of the pre and post cats O2 sensors. Those are also referred to as the upstream and downstream O2 sensors. If you're getting the same readings, that means the cat isn't doing anything and it's bad.

 

[daves66nova]

Originally Posted By: Gasbuggy
This is my area of expertise. You'll get that code at just 10% below ideal, so you're not killing trees getting around it. If you throw a gallon of mineral spirits in about a half tank of gas that code will go away after a 2-3 driving cycles.
what I recently did was swap the sensors behind each of the pre cats and the same code again,430, to ascertain if it{hopefully} would of been a sensor. If I do the gallon of Mineral Spirits,will it mess up any plastic,rubber seals,etc? I don't want to fix one problem only to create another problem.Also, how long will this make the code go away for?