Tip & How-To about Motorcycles
P0431 - Warm Up Catalyst Efficiency Below Threshold (Bank 2)
Basically this means that the oxygen sensor downstream of the catalytic converter on bank 2 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.
Symptoms: You will likely not notice any drivability problems, although there may be symptoms such as a rough/hard idle when cold.
Causes: A code P0431 may mean that one or more of the following has happened:
* The catalytic converter is no longer functioning properly
* An oxygen sensor is not reading (functioning) properly
* There is an exhaust leak
Possible Solutions: Inspect for exhaust leaks. Next step is to measure the voltage at the oxygen sensor on Bank 2. In fact, it would be a good idea to test each oxygen O2 sensor while you're at it.
One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.
Hope helps (remember to arte and comment this).
Posted by Computer... on
Oct 06, 2013 | 2004 Kia Sedona
hi,my friend, you can try,
Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.
Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).
Inspect the downstream heated oxygen sensor (HO2), replace if necessary
Replace the catalytic converter
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