Faulty bank 2 sensor 3 heated oxygen sensor (HO2S) reading rich when the mixture is actually normal; Exhaust leak before or near the sensor allowing outside air to skew the reading; Wiring damage or corrosion in the sensor circuit causing a high-voltage signal; A stuck-open or leaking fuel injector on bank 2 enriching the mixture; High fuel pressure from a failed fuel pressure regulator or restricted return line; A contaminated mass airflow sensor over-reporting airflow and causing excess fuel delivery; A restricted air filter or intake blockage reducing airflow and enriching the mixture

DTC codes / Chrysler codes / P1164

P1164 · ChryslerHO2S Bank 2 Sensor 3 Rich Or High Voltage

Q: What does code P1164 mean?

HO2S Bank 2 Sensor 3 Rich Or High Voltage. P1164 on a Chrysler vehicle means the powertrain control module has detected that the downstream heated oxygen sensor (HO2S) on bank 2, sensor 3, is reporting a rich condition or a voltage that stays higher than expected. The computer compares this signal against its expected range and sets the code when the sensor output remains elevated for a calibrated period.

P1164 on a Chrysler vehicle means the powertrain control module has detected that the downstream heated oxygen sensor (HO2S) on bank 2, sensor 3, is reporting a rich condition or a voltage that stays higher than expected. The computer compares this signal against its expected range and sets the code when the sensor output remains elevated for a calibrated period.

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 commanded
Occasional rough idle or hesitation when the mixture is excessively rich
A sulfur or rotten-egg smell from the exhaust in severe cases
Black sooty exhaust smoke under heavy acceleration if the rich condition is pronounced

Common causes, most likely first

Faulty bank 2 sensor 3 heated oxygen sensor (HO2S) reading rich when the mixture is actually normal
Exhaust leak before or near the sensor allowing outside air to skew the reading
Wiring damage or corrosion in the sensor circuit causing a high-voltage signal
A stuck-open or leaking fuel injector on bank 2 enriching the mixture
High fuel pressure from a failed fuel pressure regulator or restricted return line
A contaminated mass airflow sensor over-reporting airflow and causing excess fuel delivery
A restricted air filter or intake blockage reducing airflow and enriching the mixture

How to diagnose and fix it

Connect a scan tool and record freeze-frame data and HO2S voltage readings to confirm the rich condition
Visually inspect the bank 2 sensor 3 wiring and connector for chafing, corrosion, or loose pins
Check for exhaust leaks upstream of the sensor using a smoke test or listening for ticking
Measure fuel pressure and compare it to the manufacturer's specification
Perform an injector balance test or inspect spark plugs on bank 2 for rich fouling
Swap the bank 2 sensor 3 with a known-good sensor to see if the code follows the sensor
Replace the faulty HO2S or repair the circuit fault, then clear codes and verify the repair with a road test

When the sensor is not the real culprit

A rich-reading downstream oxygen sensor often indicates a problem upstream, such as a leaking injector or high fuel pressure, so replacing the sensor first can waste money.
Exhaust leaks between the engine and the sensor pull in outside oxygen and can make the sensor report a false lean or rich condition depending on the leak location.
Chrysler's bank 2 sensor 3 is typically a downstream sensor on the second bank, and its voltage should oscillate slowly; a steady high voltage suggests a rich mixture or a shorted signal circuit.
A contaminated mass airflow sensor can cause a rich condition on both banks, but the code may set only for bank 2 if the contamination is uneven or the bank 2 sensor is more sensitive.
After repairs, the PCM may need several drive cycles to relearn fuel trim, so the code may not clear immediately even when the fault is fixed.

Can I keep driving with P1164?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy acceleration and long trips because a persistent rich condition can damage the catalytic converter and waste fuel. If the check engine light starts flashing, stop driving and seek immediate service.

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.