P0133
O2 Sensor Slow Response (Bank 1 Sensor 1)
This code means the oxygen sensor before the catalytic converter on the first bank of cylinders is responding too slowly to changes in the exhaust gas. This sensor helps the engine adjust its fuel mixture, so a slow response can lead to inefficient operation.
O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)
Common causes
- high
Aging/Contaminated O2 Sensor (Bank 1 Sensor 1)
Over time, the sensor can become sluggish due to carbon buildup or internal degradation, causing it to react slowly.
Typical part cost: $50-200 part
- medium
Exhaust Leaks
Leaks near the sensor can dilute the exhaust gas, making the sensor respond inaccurately or slowly.
Typical part cost: $50-300 repair
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First things to check
- 1Visually inspect the O2 sensor and its wiring for any damage or signs of contamination.
- 2Check for exhaust leaks upstream of the Bank 1 Sensor 1.
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Related codes
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Frequently asked questions
What does 'slow response' mean for an O2 sensor?
It means the sensor isn't changing its voltage signal quickly enough in response to changes in the exhaust gas composition, which is necessary for the engine to maintain an optimal air/fuel ratio.
Can a P0133 code affect my car's power?
Yes, because the engine's computer can't accurately adjust the fuel mixture, it might run less efficiently, leading to a noticeable decrease in power or acceleration.
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