P0158 means the Engine Control Module (ECM/PCM) has detected a higher-than-expected voltage from the oxygen sensor circuit for Bank 2 Sensor 2. Sensor 2 is normally the downstream oxygen sensor located after the catalytic converter.
P0158 Location by Manufacturer
The exact location of P0158 depends on the vehicle's year, engine, and exhaust configuration. Bank 2 is the cylinder bank opposite the bank containing cylinder number one, while Sensor 2 normally refers to the downstream oxygen sensor.
Chevrolet Silverado
On V8 applications, P0158 refers to Bank 2 Sensor 2, the downstream oxygen sensor on the Bank 2 exhaust side. The exact physical position depends on the engine and model year.
Toyota
Bank 2 Sensor 2 is normally the downstream oxygen sensor on the Bank 2 exhaust side. Location varies with engine configuration.
Nissan
On applicable V-type engines, Bank 2 Sensor 2 is the downstream oxygen sensor for Bank 2. Verify the exact position using the vehicle's service information.
Jeep Wrangler
On applicable V-type engines, P0158 concerns Bank 2 Sensor 2 after the catalytic converter. The side and exact position vary by engine and model year.
Important: Do not identify the sensor by driver or passenger side alone. Always confirm Bank 2 and Sensor 2 for the specific year and engine.
Symptoms of P0158
Check Engine Light
The Check Engine Light may illuminate after the ECM stores P0158.
Poor Fuel Economy
Fuel economy may decrease, especially if the high sensor reading is related to a rich-running condition.
Rough Running
Some vehicles may experience rough idle, hesitation, or reduced performance.
Increased Emissions
An oxygen sensor or mixture problem can increase exhaust emissions.
Common Causes of P0158
Faulty O2 Sensor
The Bank 2 Sensor 2 oxygen sensor may produce an abnormally high signal.
Shorted Signal Wire
A damaged signal wire contacting a power circuit can force the sensor voltage high.
Damaged Connector
Corrosion, loose terminals, or damaged pins can affect the sensor signal.
Rich Fuel Mixture
Excess fuel in the exhaust can produce a genuinely high oxygen sensor signal.
Leaking Fuel Injector
A leaking injector can create an excessively rich mixture.
High Fuel Pressure
Fuel pressure above specification can cause excessive fuel delivery.
Estimated Repair Cost for P0158
O2 Sensor
$100–$300 approximately.
Wiring Repair
$50–$250 approximately.
Fuel System Repair
$150–$800+ depending on the failed component.
Catalytic Converter
$500–$2,500+ depending on vehicle and parts used.
These are general estimates only. Actual cost depends on the vehicle, parts, labor rate, and the cause of P0158.
How to Fix P0158
Diagnose the cause before replacing any components. Inspect the Bank 2 Sensor 2 wiring and connector, check the sensor signal, and verify that the signal wire is not shorted to battery voltage. If the circuit is correct, check for an actual rich-running condition.
- Repair damaged oxygen sensor wiring.
- Repair corroded or loose connector terminals.
- Replace the oxygen sensor if testing confirms it is faulty.
- Repair leaking fuel injectors or excessive fuel pressure when present.
- Clear the code and verify the repair with live data and a road test.
Common Repair Mistakes
Replacing the Sensor Immediately
P0158 does not automatically mean the oxygen sensor is defective.
Ignoring the Wiring
A shorted signal wire can create the same high-voltage condition.
Ignoring a Rich Condition
An actual fuel-system problem can produce a high oxygen sensor signal.
Replacing the Wrong Sensor
Confirm Bank 2 Sensor 2 before replacing an oxygen sensor.
Assuming the Same Location on Every Vehicle
Sensor location varies by manufacturer, model year, and engine.
P0158 FAQ
What does P0158 mean?
P0158 means the oxygen sensor circuit for Bank 2 Sensor 2 is reporting a higher-than-expected voltage.
Is P0158 always a bad oxygen sensor?
No. Wiring faults, connector problems, and a rich-running engine can also cause P0158.
Where is Bank 2 Sensor 2 located?
It is normally the downstream oxygen sensor after the catalytic converter on Bank 2. The exact location depends on the vehicle and engine.
Can I drive with P0158?
The vehicle may remain drivable, but the fault should be diagnosed promptly, especially if the engine is running rich.
How do I fix P0158?
Inspect the wiring and connector, test the sensor signal, and check for an underlying rich fuel condition before replacing parts.
Can P0158 affect fuel economy?
Yes. Fuel economy can be affected when P0158 is associated with an incorrect fuel mixture or related engine problem.
Final Result
P0158 indicates a high-voltage condition involving Bank 2 Sensor 2. Correct diagnosis should verify the sensor, wiring, connector, and engine fuel mixture before replacing components.