Engine-Codes - Infiniti - P1166 2003 INFINITI G35

P1166 2003 INFINITI G35 - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 2

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

P1166 2003 INFINITI G35 Possible Causes

  • Faulty heated oxygen (O2) sensor 2 (rear)
  • Intake air leaks
  • Heated oxygen (O2) sensor 2 (rear) harness is open or shorted
  • Heated oxygen (O2) sensor 2 (rear) circuit poor electrical connection
  • Inappropriate fuel pressure
  • Faulty fuel injectors

How do I fix code P1166 2003 INFINITI G35

Check 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

Replacing the O2 Sensor 2 usually takes care of the problem

Cost of diagnosing the P1166 2003 INFINITI G35 code

Labor: 1.0

The cost of diagnosing the P1166 2003 INFINITI G35 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.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • High Fuel Consumption
  • Excessive Smoke from Exhaust

P1166 2003 INFINITI G35 Meaning

The Heated Oxygen Sensor 2 (HO2S) (Rear O2 Sensor), 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.

P1166 2003 INFINITI G35 More Information

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