O2 Sensor Circuit High Voltage (Bank 2 Sensor 3)
The P0164 code indicates that the oxygen sensor located after the catalytic converter on Bank 2 (the side of the engine not containing cylinder #1) is reporting a voltage signal that is higher than the expected range (typically above 1.0 volt). This sensor monitors the efficiency of the catalytic converter. A high voltage condition can be caused by a faulty sensor, wiring issues, or an exhaust leak. If left unresolved, it can lead to poor fuel economy and increased emissions.
01. Most Common Causes
- Faulty oxygen sensor (Bank 2 Sensor 3)
- Short to voltage in the sensor wiring or connector
- Exhaust leak upstream of the sensor
- Engine vacuum leak causing rich fuel mixture
- Faulty PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Poor fuel economy
- Failed emissions test
- Rough idle or hesitation
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for other codes.
Step 2: Visually inspect the O2 sensor wiring and connector for damage, corrosion, or shorts.
Step 3: Check for exhaust leaks near the sensor using a smoke machine or listening for hissing.
Step 4: Test the sensor voltage with a multimeter; compare to manufacturer specifications.
Step 5: If voltage is consistently high, replace the oxygen sensor.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
You can drive short distances, but it may cause poor fuel economy and increased emissions. Prolonged driving could damage the catalytic converter.
How much does it cost to fix?▼
Replacing the oxygen sensor typically costs $150-$300 including parts and labor. Diagnosis may add $50-$100.