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 computer thinks the oxygen sensor in the exhaust system is sending signals that are too strong. It's like if your teacher thinks you're yelling when you're just talking normally.
The OBD-II code P1149 indicates that the oxygen sensor located after the catalytic converter on the second bank of the engine is reporting higher than expected voltage signals.
The P1149 code is triggered when the Engine Control Module (ECM) detects that the signal from the oxygen sensor on Bank 2 Sensor 2 is consistently higher than the expected range. This sensor is responsible for monitoring the efficiency of the catalytic converter by measuring the oxygen level in the exhaust gases. A high signal could indicate an issue with the sensor itself or with the exhaust system.
• Check Engine Light illuminated
• Poor fuel economy
• Failed emissions test
• Faulty oxygen sensor
• Wiring issues or poor connections
• Exhaust leaks affecting sensor readings
ECM: Engine Control Module
Oxygen Sensor: A device that measures the oxygen level in the exhaust gases
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the oxygen sensor.
• Test the oxygen sensor's voltage output with a multimeter.
• Replace the faulty oxygen sensor.
• Repair or replace damaged wiring or connectors.
• Fix any exhaust leaks.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $300
Moderate
• Honda Accord
• Nissan Altima
• Toyota Camry
• Regularly inspect and maintain the exhaust system.
• Use high-quality fuel to prevent sensor contamination.
• Schedule regular vehicle check-ups.
Sensor Issue
• Address the issue promptly to avoid further damage.
• Consult a professional mechanic if unsure about repairs.
Oxygen sensors may be covered under the vehicle's emissions warranty.
P1149 is a less common code but can occur in vehicles with aging oxygen sensors or exhaust issues.
Moderate – It should be addressed soon to prevent further issues.
Ignoring this code could lead to increased emissions and potential legal issues in areas with strict emission laws.
• Engine at operating temperature
• Vehicle running at idle
The oxygen sensor is located in the exhaust system after the catalytic converter on the side of the engine with the second bank of cylinders.
Q: Can I drive with a P1149 code?
A: It's possible to drive short distances, but it's best to fix the issue soon to avoid further damage.
Q: Will a P1149 code affect my car's performance?
A: Yes, it can lead to poor fuel economy and increased emissions.
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.