2000 Infiniti I30 P0430 Trouble Code

Well, use a diagnostic scan tool, read the data for the oxygen sensors, compare b2s1 and b2s2, as long as the readings are not mimic one another, meaning, identical, then oxygen sensor is okay, doing its job measuring, you would then look for other possible causes, such as, exhaust leaks, air intake leaks, timing, fuel injectors, or fuel injector leaks, spark plugs condition.