How do I fix code po421?

Repairs that can fix the P0421 code may include:

1. Replacing the catalytic converter.
2. Replacing the oxygen sensor.
3. Repairing or replacing wiring that is associated with the oxygen sensor.
4. Replacing the powertrain control module.

What is code po421?

Overview. Error Code P0421 is described as Warm Up Catalyst Efficiency Below Threshold (Bank 1). This means the Catalytic Converter’s Oxygen Sensor Downstream has detected that the Bank 1 converter is not working properly.

What to do if your Mitsubishi Lancer has a p0421 code?

Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0421 code is combined with other codes, try fixing the other codes first. There is a factory service recall for the following Mitsubishi Models: 2002 Mitsubishi Lancer 2003 Mitsubishi Lancer

What to do if your car has trouble code po420?

Fill out the warranty card. When a vehicle is exhibiting one of these codes (or variations of these, such as P0421/P0431) you can prevent a lot of headaches if you’ll follow these simple steps. First, if ANY other OBDII codes are present, address them first.

What does the code po431 mean on a catalytic converter?

All that code says is either Converter operating below efficency or Converter operating below threshold. Nowhere in the interpretation of that code does it say the converter is bad. Your vehicle may very well need a Catalytic Converter but to determine this, your mechanic or technician should perform proper engine diagnostics.

What to do if your OBD code is p0421?

Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0421 Mitsubishi code is combined with other codes, try fixing the other codes first. What about the obd code?