P0433 Fault Code

Heated Catalyst Efficiency Below Threshold (Bank 2)

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0433 fault code indicates that the engine control module (ECM) has detected that the heated catalyst efficiency for Bank 2 is below the expected threshold. This condition can impact the performance of the catalytic converter and can lead to increased emissions.

• This code is often associated with vehicles equipped with a dual exhaust system, where each bank has its own catalytic converter.
• The code suggests that the efficiency of the catalyst in converting harmful exhaust gases is insufficient, potentially due to various underlying issues.

What are the symptoms of the P0433 code?

Common symptoms associated with a P0433 fault code include:

• Illuminated check engine light.
• Failed emissions test.
• Reduced engine performance.
• Increased fuel consumption.
• Unusual odor from the exhaust system.

What causes the P0433 code?

Several factors can contribute to a P0433 code:

• A malfunctioning or damaged catalytic converter on Bank 2.
• Faulty oxygen sensors that monitor the catalyst’s performance.
• Exhaust leaks before or after the catalytic converter, affecting readings.
• Engine misfires leading to abnormal exhaust composition.
• Incorrect fuel mixture, leading to inefficient combustion.

How to fix P0433?

To address the P0433 fault code, consider the following steps:

• Start by reading the vehicle’s diagnostic trouble codes (DTCs) to confirm the issue.
• Inspect oxygen sensors on Bank 2 and replace if necessary.
• Check for exhaust leaks around the catalytic converter and repair as needed.
• Conduct a visual inspection of the catalytic converter for damage or clogging.
• If the catalytic converter is faulty, replace it to restore proper function.