P0420 - OBD Trouble Code

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How does an OBD code P0420 occur? What does a catalytic converter do? Should you not know about this? So here it is. During the combustion cycle, the catalytic converter breaks downs every of the harmful pollutants that are being created. The catalytic converter reduces the emissions with the help of fine platinum and gold meshes by which it filters the exhaust fumes and is expelled from the exhaust pipe.

When the readings are similar to each other in the oxygen sensor, then it is a sign of indication that the catalytic converter is not performing as expected. When the downstream oxygen sensor shows a decrease in voltage, and starts fluctuating similar to the upstream oxygen sensor, then this concludes the high level of oxygen and the P0420 trouble code will be stored by the Powertrain Control Module (PCM).

What causes this problem with the Catalyst System Efficiency Below Threshold?

• Muffler that is either damaged or leaky
• Faults in the exhaust manifold or a leaky exhaust manifold
• Broken exhaust pipes or a leak in the exhaust pipe
• A backfire in the engine
• Contamination of oil in the catalytic converter
• Damaged catalytic converter (most probably)
• Fault in the engine coolant temperature sensor
• Damaged front oxygen sensor
• Damaged rear oxygen sensor
• Fault with the oxygen sensor wires
• Broken connectors of the oxygen sensor
• A leaky fuel injector
• A high fuel pressures
• By using the wrong kind of fuel (usage of leaded fuel rather than unleaded fuel)

1. Oxygen Sensor - A fault in the front and rear oxygen sensor can be one of the reasons for this error. Replaced the damaged / faulty parts as soon as possible.
2. Connector - You need not worry if your connectors are broken or damaged. You can get them at the best prices online from PartsAvatar.
3. Fuel Injector - A leaky fuel injector can damage your engine system. Visually inspect the component and replace or repair them at once.
4. Catalytic Converter - Is there any fault or leak with your catalytic converter? Is there too much of oil contamination? If your answer is yes, get rid of them with the right parts from Parts Avatar.

For us our customers are everything, and that’s why we will help you to diagnose P02BA code by mentioning some important symptoms below:

Common Symptoms

• No sign of any symptoms or problems related to drive ability (most probably)
• The light of the Check engine is on
• Shortage of power after the vehicle warms up
• When the vehicle’s speed does not exceed 30-40 mph
• Pungent smell like that of a rotten egg which comes from the exhaust pipe

Here are some ways with the help of which you will be able to correct the OBD Code P0420:

• Replacing the damaged muffler or repairing the leaks in the muffler
• Repairing the leaks or damages in the exhaust manifold
• Rectifying the leaks or repairing the damages in the exhaust pipe
• A most common reason – replacing the damaged catalytic converter
• Changing the damaged engine coolant temperature sensor
• Substituting with a good front and rear oxygen sensor connectors
• Replacing or repairing the leaky fuel injectors
• Diagnosing the damaged parts and problems due to misfire
• Checking and rectifying the other trouble codes which are stored by the Powertrain Control Module (PCM)

There is no need to be anxious as Parts Avatar – Car Parts Online is here to help you out! We have high grade Oxygen Sensor. Connectors, Fuel Injector, Catalytic Converter and a lot more for our precious customers.

Here are some steps which you should follow in order to diagnose this fault code:

• Initially, the mechanic will use an OBD – II scanner to recover all the trouble codes that are stored by the PCM.
• Next is to check the live data of downstream that is rear oxygen sensor. The reading of the downstream oxygen sensor has to be stable. Make sure as to if the rear oxygen sensor is functioning effectively.
• Check for other troubles and diagnose the codes that cause P0420 error
• If there are any problems related to ignition, fuel system, or misfires repair them if needed
• Check for damages in the rear oxygen sensor and unnecessary wear
• View the freeze frame data and, test drive the vehicle to see if or not the rear oxygen sensor is functioning properly.
• If there are any faults in the catalytic converter, check for updates of the PCM. Once the catalytic converter is updated with new parts, you have to now update the PCM.

Common Mistakes When Diagnosing the P0420 Code

One of the most common mistakes which gives rise to this error is, replacing the oxygen sensors even before the diagnostic process is completed. If you replace the oxygen sensor when the problem is caused by some other component, fixing the oxygen sensors won’t solve the issue.