📖 What Does P0139 Mean?
The downstream oxygen sensor on bank 1 is responding too slowly to exhaust changes.
Symptoms
Failed emissions test, check engine light, poor catalytic converter monitoring.
Common Causes
Aging oxygen sensor, contaminated sensor, exhaust leaks, poor sensor connections.
Possible Solutions
Replace oxygen sensor, repair exhaust leaks, clean sensor connections, check sensor ground.
Recommended Parts & Tools
Find the right parts for your P0139 repair on Amazon
📦 Parts Needed
💡 Pro Tip: Always verify part compatibility with your specific vehicle year, make, and model before purchasing.
As an Amazon Associate, CarMedic earns from qualifying purchases. This helps us maintain our free diagnostic database.
Frequently Asked Questions about P0139
How serious is P0139?
This code has a medium severity level. This should be diagnosed and repaired soon to prevent further issues.
Can I drive with P0139?
You can typically drive short distances, but have it diagnosed as soon as possible.
How much does it cost to fix P0139?
Repair costs vary depending on the root cause, but typically range from $100-300 including parts and labor.
Related Diagnostic Codes
Other codes that may appear with P0139
Fuel and Air Metering Code P0100
Mass Air Flow Sensor Circuit Range/Performance Problem
Mass Air Flow Sensor Circuit Low Input
Mass Air Flow Sensor Circuit High Input
Fuel and Air Metering Code P0104
Fuel and Air Metering Code P0105
💡 Why These Codes Are Related:
- • Similar Issues: Same root cause or component failure
- • Related Problems: Often occur together due to system interactions
- • Sequential Codes: Progressive failure stages or multiple sensors
- • Same System: Components within the same automotive system