AutoCodes – Pontiac – P0140 Pontiac

P0140 Pontiac Code - O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2

Quick Answer

The heated oxygen sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

What it means: P0140 Pontiac indicates O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2.
Common causes: Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection.
Severity: Moderate - service should be scheduled soon.
Can I drive?: The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

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Code Popularity 18,405

How popular is this code, among other codes? Low

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 12, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0140 Pontiac Description

The heated oxygen sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air fuel mixture (air-fuel ratio) must be maintained near the ideal stoichiometric ratio. The HO2S output voltage changes suddenly in the vicinity of the stoichiometric ratio. The Engine Control Module (ECM) adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S generates a voltage between 0.1 and 0.9 V in response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The ECM interprets Lean when the HO2S voltage is below 0.45 V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The ECM interprets Rich when the HO2S voltage is above 0.45 V.

OBDII Code P0140 Pontiac - O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2 - AutoCodes.com — P0140 Pontiac Code - O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2

What does this mean?

What are the Possible Causes of the DTC P0140 Pontiac?

Faulty Rear Heated Oxygen Sensor Bank 1
Rear Heated Oxygen Sensor Bank 1 harness is open or shorted
Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection
Inappropriate fuel pressure
Faulty fuel injectors
Intake air leaks may be faulty
Exhaust gas leaks

How to Fix the DTC P0140 Pontiac?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0140 Pontiac code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0140 Pontiac Code

1. What are the common symptoms of OBDII code P0140 in a Pontiac related to the O2 sensor circuit?

- Common symptoms include poor fuel economy, rough idling, hesitation during acceleration, and the illumination of the check engine light.

2. What does the OBDII code P0140 Pontiac O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2 indicate?

- This code indicates that the O2 sensor located after the catalytic converter on bank 1 (side of the engine with cylinder 1) is not sending any signal or has very low activity.

3. What are the possible causes of the O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2 code in a Pontiac?

- Possible causes include a faulty O2 sensor, damaged wiring or connectors in the O2 sensor circuit, exhaust leaks, or a failed catalytic converter.

4. How can I diagnose the O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2 code in my Pontiac?

- Diagnose the code by visually inspecting the O2 sensor and its wiring, checking for exhaust leaks, using a scan tool to monitor O2 sensor data, and performing voltage tests on the sensor.

5. Can I drive my Pontiac with the P0140 OBDII code?

- It is not recommended to drive your Pontiac with this code for an extended period as it can lead to decreased fuel efficiency and potential damage to the catalytic converter.

6. How can I repair the O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2 code in my Pontiac?

- Repair options include replacing the faulty O2 sensor, repairing damaged wiring or connectors, fixing any exhaust leaks, and addressing any issues with the catalytic converter.

7. Will resetting the check engine light fix the P0140 code in my Pontiac?

- Resetting the check engine light may temporarily clear the code, but it will likely return if the underlying issue with the O2 sensor circuit is not properly diagnosed and repaired.

8. How much does it typically cost to repair the OBDII code P0140 in a Pontiac?

- The cost of repairs can vary depending on the specific issue causing the code, but it may range from $100 to $300 for parts and labor.

9. Are there any DIY tips for addressing the P0140 code in a Pontiac?

- DIY tips include checking and cleaning O2 sensor connectors, inspecting for visible damage in the wiring, and ensuring the sensor is properly secured in place.

10. Can a faulty O2 sensor cause other problems in my Pontiac if left unrepaired?

- Yes, a faulty O2 sensor can lead to decreased fuel efficiency, increased emissions, poor engine performance, and potential damage to the catalytic converter if left unrepaired.