Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's pollution-fighting part, called the catalytic converter, isn't working well enough on one side of the engine. It's like a filter that's not cleaning as much as it should.
The P0422 code indicates that the catalytic converter on bank 1 is not reducing emissions as efficiently as expected.
The P0422 code is triggered when the Engine Control Module (ECM) detects that the catalytic converter's efficiency on bank 1 is below the threshold set by the manufacturer. This is usually monitored by the oxygen sensors before and after the catalytic converter.
• Check Engine Light is on
• Increased emissions
• Potential decrease in fuel efficiency
• Faulty catalytic converter
• Damaged or faulty oxygen sensor
• Exhaust leaks
Catalytic Converter: A device that reduces harmful emissions from the engine exhaust.
Oxygen Sensor: A sensor that measures the oxygen level in the exhaust gases to help the engine run efficiently.
• Use an OBD-II scanner to confirm the code
• Inspect the catalytic converter for damage
• Check oxygen sensor readings
• Replace the catalytic converter
• Replace faulty oxygen sensors
• Repair any exhaust leaks
• OBD-II scanner
• Wrench set
• Multimeter
$500 - $2000
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regular vehicle maintenance
• Use high-quality fuel
• Avoid short trips that don't allow the engine to warm up
Engine Performance
• Get the issue diagnosed and repaired promptly to avoid further damage.
• Consider using a higher octane fuel if recommended by the manufacturer.
Catalytic converters are often covered under the emissions warranty, which may last up to 8 years or 80,000 miles.
The P0422 code has been a common issue as vehicles age and catalytic converters wear out, especially in vehicles with high mileage.
Moderate – While the car may still drive, emissions are increased, and fuel efficiency may be affected.
Driving with a faulty catalytic converter can increase emissions and may be illegal in areas with strict emissions regulations.
• Engine at operating temperature
• Vehicle driven at various speeds for a complete drive cycle
The catalytic converter is located in the exhaust system, usually between the exhaust manifold and the muffler.
Q: Can I drive with a P0422 code?
A: Yes, but it's not recommended due to increased emissions and potential legal issues.
Q: Will a P0422 code affect my car's performance?
A: It may lead to decreased fuel efficiency and increased emissions, but performance might not be noticeably affected.
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Fitment Required · Vehicle-fitment part
Relevant when the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.