Engine-Codes - Nissan - P1143 2002 NISSAN SENTRA

P1143 2002 NISSAN SENTRA - Heated Oxygen Sensor 1 Lean Shift Monitoring Bank 1

Repair Importance Level: 3/3
Repair Difficulty Level: 2/3  What is this?
Table of contents

P1143 2002 NISSAN SENTRA Possible Causes

  • Faulty Front Heated Oxygen Sensor Bank 1
  • Intake air leaks
  • Front Heated Oxygen Sensor Bank 1 harness is open or shorted
  • Front Heated Oxygen Sensor Bank 1 circuit poor electrical connection
  • Fuel pressure
  • Injectors

How is the P1143 2002 NISSAN SENTRA code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Tech Notes

If there are no intake air leaks, the most likely cause of the P1143 code is the front O2 sensor bank 1.

What is the cost to diagnose the P1143 2002 NISSAN SENTRA code

Labor: 1.0

The cost to diagnose the P1143 2002 NISSAN SENTRA code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
How much do you know about cars?

Take the AutoCodes.com automotive tests and turbo-charge your car repair knowledge

Play Now

When is the code detected?

The maximum and minimum voltage from the sensor are not reached to the specified voltages.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P1143 2002 NISSAN SENTRA Meaning

The Heated Oxygen Sensor 1 is placed into the front tube. It detects the amount of oxygen in the exhaust gas compared to the outside air. The heated oxygen sensor 1 has a closed-end tube made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions. The heated oxygen sensor 1 signal is sent to the Engine Control Module (ECM). The ECM adjusts the injection pulse duration to achieve the ideal air-fuel ratio. The ideal air-fuel ratio occurs near the radical change from 1V to 0V.

More Information

Need more information on how to fix the P1143 2002 NISSAN SENTRA code?
Get Access to Factory Service Manuals

Need more help?

Get the P1143 2002 Nissan Sentra code diagnosed by a professional: Find a repair shop in your area