AutoCodes – Generic – P1165

P1165 Code - Air/Fuel Ratio Sensor 1 Circuit Range/Performance

Quick Answer

The Air/Fuel Ratio (A/F) sensor 1 is installed in the exhaust system and detects oxygen content in the exhaust gas. Common causes include Air/Fuel Ratio Sensor 1 harness is open or shorted, Air/Fuel Ratio Sensor 1 circuit poor electrical connection, Faulty Air/Fuel Ratio Sensor 1. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1165 indicates Air/Fuel Ratio Sensor 1 Circuit Range/Performance.
Common causes: Common causes include Air/Fuel Ratio Sensor 1 harness is open or shorted, Air/Fuel Ratio Sensor 1 circuit poor electrical connection, Faulty Air/Fuel Ratio Sensor 1.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 11,722

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 04, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1165 Description

The Air/Fuel Ratio (A/F) sensor 1 is installed in the exhaust system and detects oxygen content in the exhaust gas. The A/F sensor transmits output voltage to the Engine Control Module (ECM). A heater for the sensor element is embedded in the A/F sensor (sensor 1). It is activated and heats the sensor to stabilize and speed the detection of oxygen content by controlling current flowing through the heater. An increase in the current levels off as the applied voltage to the element electrode reaches a certain range because the amount of oxygen which is led through the diffusion layer is limited. The current amperage is proportional to oxygen content in the exhaust gas, so the air/fuel ratio is detected by the measurement of the current amperage. The ECM compares a set target air/fuel ratio with the detected air/fuel ratio and controls the fuel injection timing.
If the A/F sensor (sensor 1) voltage is low, the air/fuel ratio is lean, and the ECM uses A/F feedback control to issue a Rich command. If the A/F sensor (sensor 1) voltage is high, the air/fuel ratio is rich, and the ECM uses A/F feedback control to issue a Lean command.

OBDII Code P1165 - Air/Fuel Ratio Sensor 1 Circuit Range/Performance - AutoCodes.com — P1165 Code - Air/Fuel Ratio Sensor 1 Circuit Range/Performance

What does this mean?

What are the Possible Causes of the DTC P1165?

Air/Fuel Ratio Sensor 1 harness is open or shorted
Air/Fuel Ratio Sensor 1 circuit poor electrical connection
Faulty Air/Fuel Ratio Sensor 1

How to Fix the DTC P1165?

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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1165 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.

Need more information about the P1165 code?

Need more information on how to fix the P1165 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1165 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1165 Acura — Air/Fuel Ratio Sensor 1 Circuit Range/Performance
P1165 Audi — Bank 1 Long Term Fuel Trim Range 1 Rich Upper Limits Exceeded
P1165 BMW — Fuel Trim Additve Per Ignition Bank 2 High
P1165 Buick — HO2S Cross Counts Bank 2 Sensor 3
P1165 Cadillac — HO2S Cross Counts Bank 2 Sensor 3
P1165 Chevrolet — HO2S Cross Counts Bank 2 Sensor 3
P1165 GMC — HO2S Cross Counts Bank 2 Sensor 3
P1165 Honda — Air/Fuel Ratio Sensor 1 Circuit Range/Performance
P1165 Infiniti — Swirl Control Valve Control Vacuum Switch
P1165 MINI — Fuel Trim Additve Per Ignition Bank 2 High
P1165 Nissan — Swirl Control Valve Control Vacuum Switch
P1165 Volkswagen — Bank 1 Long Term Fuel Trim Range 1 Rich Upper Limits Exceeded

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 P1165 Code

1. What are the common symptoms of OBDII code P1165 (Air/Fuel Ratio Sensor 1 Circuit Range/Performance)?

The common symptoms of P1165 may include poor fuel economy, engine misfires, rough idling, and a noticeable decrease in overall engine performance.

2. What are the possible causes of OBDII code P1165?

Possible causes of P1165 include a faulty air/fuel ratio sensor, wiring issues in the sensor circuit, exhaust leaks, or problems with the engine's fuel system.

3. How does the air/fuel ratio sensor impact the performance of the vehicle?

The air/fuel ratio sensor is a crucial component that monitors and adjusts the mixture of air and fuel entering the engine. A malfunctioning sensor can lead to improper fuel mixture, which can result in poor engine performance and decreased fuel efficiency.

4. Can I continue driving my vehicle with the P1165 trouble code?

It is not recommended to drive your vehicle with an active P1165 code, as it can lead to further damage to the engine and emissions system. It is best to address the issue promptly to avoid potential complications.

5. How can I diagnose and repair OBDII code P1165?

Diagnosing P1165 typically involves inspecting the air/fuel ratio sensor and its wiring for any visible damage. Repair may involve replacing the sensor, repairing wiring issues, or addressing any exhaust leaks present.

6. Will resetting the trouble code make it go away permanently?

Resetting the trouble code may temporarily turn off the Check Engine Light, but if the underlying issue causing P1165 is not fixed, the code is likely to return. It is essential to diagnose and repair the root cause of the problem.

7. Can a dirty air filter cause OBDII code P1165 to trigger?

While a dirty air filter can impact engine performance, it is not a direct cause of P1165. The code is typically related to issues with the air/fuel ratio sensor or its circuit.

8. How can I prevent OBDII code P1165 from recurring in the future?

Regular maintenance of your vehicle, including scheduled sensor inspections and timely repairs, can help prevent the recurrence of P1165. Ensuring the proper functioning of the air/fuel ratio sensor and related components is key.

9. Is it possible to drive with a faulty air/fuel ratio sensor?

Driving with a faulty air/fuel ratio sensor is not recommended, as it can lead to reduced fuel efficiency, engine performance issues, and potential damage to the catalytic converter over time.

10. Can a mechanic easily fix OBDII code P1165, or is it a complex repair?

The complexity of fixing P1165 can vary depending on the underlying cause. While some cases may require simple sensor replacement, more intricate issues such as wiring problems or exhaust leaks may necessitate more involved repairs by a trained mechanic.