Engine-Codes
 
OBDII Code List
 
P0140 CHEVROLET

P0140 CHEVROLET - O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2

Repair Importance Level: 2/3
Repair Difficulty Level: 2/3  What does this mean?

P0140 CHEVROLET Possible Causes

  • 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

P0140 CHEVROLET Tech Notes

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

Cost of diagnosing the P0140 CHEVROLET code

    Labor: 1.0

    The cost of diagnosing the P0140 CHEVROLET 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.

When is the P0140 CHEVROLET code detected?

The P0140 code is set when the voltage signal sent from the sensor to the Engine Control Module is constant.

P0140 CHEVROLET Possible Symptoms

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

P0140 CHEVROLET Meaning

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 CHEVROLET - O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2 - Engine-Codes.com

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