Dodge Charger P0420: Catalyst System Efficiency → Below Threshold → Bank 1

This page will help you to troubleshoot your problem. Dodge Charger P0420 trouble code. The article covers Dodge Charger P0420 definitions, symptoms, causes, as well as possible solutions. OBDII P0420 can often be caused by bad oxygen sensors in Chargers. But there may also be other reasons. You don't want to rush into replacing your O2 sensor. This can lead you to waste time and cost money.

The most common trouble code is P0420. This is the code that you get when you connect your Dodge Charger to an OBDII scanner. It doesn’t matter which model you have, this OBDII code has the same meaning for all of them (1996+)

Dodge Charger P0420 OBDII Code Defined

P0420 This is an OBDII Trouble Code. This code is technically:

The Catalyst Systems Efficiency is Below the Threshold

There are at least two oxygen sensors on your Charger. One is before the converter and one after it. They are responsible for measuring the levels of the converter's emissions.

The vehicle will light the service engine when the oxygen sensor readings show identical readings (P0420).

These readings shouldn’t match, since the catalytic converter is supposed to be scrubbing the exhaust. If the numbers are consistent, your Charger software believes the catalytic convert is not doing its job.

Dodge Charger P0420 Code Symptoms

If your oxygen sensors stop working properly, the Dodge Charger's P0420 code will be displayed. In most cases, the code will trigger the oxygen sensor that is upstream of the converter.

There aren’t usually any drivability issues associated with P0420. The first indication that something is amiss is usually the soon-light coming on in the service engine.

If you are assigned code P0420, these are common symptoms.

• Fuel Efficiency- It is possible for your catalytic converter to become clogged.
• The loss of power– It is a really strange feeling to drive a vehicle with a catalytic converter that is going out. Typically, they’ll idle ok and drive normal under a light load. Whenever the engine is put under a heavy load it’ll feel like it is running out of gas. It’s very similar to the symptoms of a bad fuel filter.
• Service Engine Light– Often, this is the only symptom of the Dodge Charger P0420 code.

Similar: P0442 Dodge Charger

Here are the Top 10 Reasons Why Dodge Chargers Have P0420

You can have the trouble code P0420 in your Charger for many reasons. Below are the top causes.

• Oxygen Sensor– The P0420 codes is thrown when the oxygen sensors on both sides of the exhaust have very similar readings. If the oxygen sensor fails, the code can be triggered. If the engine does not exhibit any of the decreased performance associated with a bad catalytic converter, it very well may be the oxygen sensor (if you haven’t noticed the performance loss yet).
• Catalytic Converter– A catalytic converter is responsible for scrubbing out as much pollution as possible from the Charger’s exhaust. These can get blocked over time. Even though modern catalytic convertors are designed to last for most vehicles' lifetime, it is possible that they have become blocked.
• The O2 Sensor Wiring– Over time, the oxygen sensor wiring can go bad. This is because it is directly next to hot exhaust. Because it is far away from the ECM, the downstream oxygen sensor wiring can also be volatile. (More distance = greater chance of failure).
• Charger Timing– If your Charger is misfiring or the exhaust timing is off, this can affect the gasses that are actually going to the O2 sensors enough to cause the P0420 code to register.
• Exhaust Leak– If there’s a noticeable exhaust leak coming from the vehicle it can change what the O2 sensors register enough to throw the P0420 code.
• Motor Temp Sensor– If the computer doesn’t know what the engine temp is it’ll keep the fuel mixture rich. The O2 sensors will not see the mixture richly and could cause it to throw its sensor.

Possible Solutions to the Dodge Charger's P0420 code

P0420 can often be caused by an oxygen sensor. Specifically it’ll usually be the O2 sensor(s) on the upstream side of the catalytic converter.

But, don’t be surprised if it’s not. You should check your exhaust first for any leaks. An exhaust leak should sound easily beneath the car.

Unless you have an exhaust leak, you’ll probably need to test the O2 sensors and/or catalytic converters. These are some great guides that will help you.

It's your task to find the cause of P0420 in your Dodge Charger. You can comment on the article or send a message if there are inaccuracies or any suggestions. Many thanks.