A failed downstream heated oxygen sensor (HO2S) on bank 2 that is stuck at a high voltage; A short to voltage or chafed signal wire between the bank 2 sensor 2 and the powertrain control module; A leaking or stuck-open fuel injector on bank 2 causing a genuine rich condition; High fuel pressure from a faulty fuel pressure regulator or restricted return line; A contaminated sensor from excessive oil or coolant consumption, or from silicone poisoning; An exhaust leak before the sensor that draws in outside air and skews the reading; A rare powertrain control module internal fault misreading the sensor signal

DTC codes / Chrysler codes / P1158

P1158 · ChryslerHO2S Bank 2 Sensor 2 Rich Or High Voltage

Q: What does code P1158 mean?

HO2S Bank 2 Sensor 2 Rich Or High Voltage. P1158 on a Chrysler vehicle means the powertrain control module has detected that the downstream heated oxygen sensor on bank 2 is reporting a rich exhaust condition or a voltage that stays higher than expected. The computer compares this signal against its expected range and flags the code when the sensor output indicates excess fuel or an abnormally high voltage for too long.

P1158 on a Chrysler vehicle means the powertrain control module has detected that the downstream heated oxygen sensor on bank 2 is reporting a rich exhaust condition or a voltage that stays higher than expected. The computer compares this signal against its expected range and flags the code when the sensor output indicates excess fuel or an abnormally high voltage for too long.

SystemPowertrain

Code typeChrysler specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
A slight decrease in fuel economy as the engine runs richer than necessary
A faint sulfur or rotten egg smell from the exhaust in some cases
Occasional rough idle or hesitation when the mixture is excessively rich
Failed emissions inspection due to the stored code and rich condition

Common causes, most likely first

A failed downstream heated oxygen sensor (HO2S) on bank 2 that is stuck at a high voltage
A short to voltage or chafed signal wire between the bank 2 sensor 2 and the powertrain control module
A leaking or stuck-open fuel injector on bank 2 causing a genuine rich condition
High fuel pressure from a faulty fuel pressure regulator or restricted return line
A contaminated sensor from excessive oil or coolant consumption, or from silicone poisoning
An exhaust leak before the sensor that draws in outside air and skews the reading
A rare powertrain control module internal fault misreading the sensor signal

How to diagnose and fix it

Connect a scan tool and record freeze-frame data and fuel trim values to confirm the rich condition on bank 2
Visually inspect the bank 2 sensor 2 wiring harness for chafing, corrosion, or a short to voltage, and repair as needed
Check fuel pressure with a gauge and compare it to the Chrysler specification for your engine
Perform a cylinder balance or injector leak-down test to identify a leaking injector on bank 2
Swap the bank 2 sensor 2 with a known-good sensor or use a lab scope to verify the sensor's voltage response
Replace the bank 2 downstream heated oxygen sensor if testing confirms it is stuck high or slow to respond
Clear the code and complete a drive cycle to verify the repair and ensure the code does not return

Why a rich code is not always the sensor

A genuine rich exhaust condition from a leaking injector or high fuel pressure will set this code even when the oxygen sensor is perfectly healthy, so always check fuel trims before condemning the sensor.
Chrysler downstream sensors on bank 2 are often misdiagnosed because technicians replace the sensor without checking for a shorted signal wire that holds the voltage high.
An exhaust leak upstream of the sensor can pull in oxygen and cause a lean reading, but a leak after the sensor or a restricted exhaust can trap rich gases and trigger this code.
Oil or coolant contamination from a failing head gasket or worn valve guides can coat the sensor and make it read rich, so inspect for contamination before installing a new sensor.
The powertrain control module uses the downstream sensor mainly to monitor catalytic converter efficiency, so a rich code on bank 2 sensor 2 can sometimes be an early warning of converter damage rather than a sensor fault.

Can I keep driving with P1158?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy acceleration or long trips because the rich condition can overheat and damage the catalytic converter. Have the fault diagnosed promptly to prevent more costly repairs.

Tools that help

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Guidance is general and written for Chrysler vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.