AutoCodes
 
OBDII Code List
 
P0161 ACURA

P0161 ACURA - O2 Sensor Heater Circuit Malfunction Bank 2 Sensor 2

Repair Importance Level: 2/3
Repair Difficulty Level: 2/3   
Comments  |  Add Comment

Possible causes

  • Faulty Rear Heated Oxygen Sensor Bank 2
  • Rear Heated Oxygen Sensor Bank 2 harness is open or shorted
  • Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection
  • Inappropriate fuel pressure
  • Faulty fuel injectors
  • Intake air leaks may be faulty
  • Exhaust gas leaks

Tech notes

Replacing the Rear Heated Oxygen Sensor Bank 2 usually takes care of the problem

When is the code detected?

Current amperage in the rear heated oxygen sensor heater circuit is out of the normal range.

Possible symptoms

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

P0161 Acura 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 P0161 Acura - O2 Sensor Heater Circuit Malfunction Bank 2 Sensor 2 - AutoCodes.com

Need more help?

Get the P0161 Acura code diagnosed by a professional: Find a repair shop in your area

Related Information

P0161 ACURA Comments

Help us improve AutoCodes.com. Leave a comment below or tell us if the information above help you fix the code. What are the symptoms on your vehicle for the P0161 Acura code? Have you replaced any parts?
Any information is appreciated. Thanks
Top ⇧