Question

What is code P0420 Ford?

Ford code P0420 is defined as “Catalyst System Efficiency Below Threshold (Bank 1),” implying the efficiency of the catalytic converter in Bank 1 is below the needed threshold.

When this code logs in your Ford car, it indicates that the catalytic converter isn’t efficiently converting toxic exhaust gases into harmless substances. The issue usually happens because of a misfire or other problems with the oxygen sensor (O2) system.

What are the common symptoms of a P0420 Ford?

The most obvious symptom of DTC P0420 Ford is a lit check engine light. Also, you can observe the following symptoms when the powertrain control module (PCM) logs this error code.

• Surge in car emissions
• Engine performance drops
• Decreased fuel economy
• Engine stalls
• Rough idling
• Odor of sulfur or rotten egg
• Engine misfire

What causes the Ford code P0420?

These are some common causes of this engine code.

• Defective oxygen sensors
• Malfunctioning catalytic converter
• Faulty wires or spark plugs
• Defective emission control system
• Exhaust leakage

How to fix the P0420 code in Ford​

These are some steps you can take to fix the issue.

• Check and replace the oxygen sensors if required
• Replace wires or damaged spark plugs
• Replace the catalytic converter if it is not working properly
• If vacuum lines or EGR valves are causing a fault, repair the emission control system

Can I drive with a P0420 code in a Ford?

Technically, you can drive with this error code. The code won’t stop you from driving immediately. However, you should get the issue diagnosed quickly and make the possible repairs to avoid additional damage and failing emissions tests. The repair cost can start at $15 and can go up to $3,200 if the catalytic converter needs replacement.