P0136
O2 Sensor Circuit (Bank 1 Sensor 2)
- Severity
- Low
- Driving
- Drivable — book it in
A general fault on oxygen sensor 2 for bank 1 - a downstream sensor, sitting after the catalytic converter. Downstream sensors do not control the fuel mixture; their job is to watch how well the converter is working. So a fault here usually has little effect on how the car drives, but it will stop the module from monitoring the converter and will fail an emissions test.
Possible causes
- CommonFailed oxygen sensor
- CommonDamaged wiring or connector at the sensor
- PossibleExhaust leak near the sensor
- PossibleSensor aged out - downstream sensors are often original at high mileage
What you might notice
- Check engine light on
- Usually no change in how the car drives
- Failed emissions test
- Converter monitoring shows as not ready
What to check, in order
- Inspect the wiring and connector. Downstream sensor leads sit under the car and suffer from road salt, stone damage and corrosion.
- Check for exhaust leaks around the sensor and the joints near it.
- Watch the sensor voltage on the live data screen. A downstream sensor on a healthy converter should be relatively steady, not oscillating like the upstream one.
- If the car has high mileage and the sensor is original, age is a reasonable explanation.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Fuel and air metering
P0100P0101P0102P0103P0104P0105P0106P0107P0108P0109P0110P0111P0112P0113P0114P0115P0116P0117P0118P0119P0120P0121P0122P0123P0124P0125P0126P0127P0128P0129P0130P0131P0132P0133P0134P0135P0136P0137P0138P0139P0140P0141P0142P0143P0144P0145P0146P0147P0148P0149P0150P0151P0152P0153P0154P0155P0156P0157P0158P0159P0160P0161P0162P0163P0164P0165P0166P0167P0168P0169P0170P0171P0172P0173P0174P0175P0176P0177P0178P0179P0180P0181P0182P0183P0184P0185P0186P0187P0188P0189P0190P0191P0192P0193P0194P0195P0196P0197P0198P0199