P1138 MERCURY – Lack of Heated Oxygen Sensor Switches The Bank 1 Sensor 2 Switch Indicates Rich

P1138 MERCURY Possible Causes

  • Exhaust gas leaks
  • Faulty Heated Oxygen Sensor 2 (HO2S2) (downstream), Bank 1
  • Open or short circuit in Bank 1 Heated Oxygen Sensor 2 wiring harness
  • Poor electrical connection in Heated Oxygen Sensor 2 circuit, Bank 1
  • Inappropriate fuel pressure
  • Faulty fuel injectors

How to Fix Code P1138 MERCURY?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Check Engine Light on (or Service Engine Soon warning light)

P1138 MERCURY Meaning

The Heated Oxygen Sensor 2 (HO2S2) (downstream), located after the three-way catalyst (manifold), monitors the oxygen level in the exhaust gases on each bank. For optimal catalyst operation, the air-fuel mixture (air-fuel ratio) must remain close to the ideal stoichiometric ratio. The HO2S2 output voltage changes abruptly near the stoichiometric ratio. The Powertrain Control Module (PCM) adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S2 generates a voltage between 0.1 and 0.9 V in response to the oxygen in the exhaust gases. If the oxygen in the exhaust gases increases, the air-fuel ratio becomes lean. The PCM interprets Lean when the HO2S2 voltage is below 0.45 V. If the oxygen in the exhaust gases decreases, the air-fuel ratio becomes rich. The PCM interprets Rich when the HO2S2 voltage is above 0.45 V.

P1138 MINI – Low voltage of O2 sensor heater circuit, bank 1 sensor 2

P1138 MINI Possible Causes

  • Faulty HO2S, Bank 1 Sensor 2
  • Open or short circuit in HO2S Bank 1 Sensor 2 wiring
  • Poor electrical connection in HO2S Bank 1 Sensor 2 circuit

How to Fix P1138 MINI Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Check Engine Light on (or soon-to-be-service engine warning light)

P1138 MINI Meaning

Low voltage in O2 sensor heater circuit, Bank 1 Sensor 2 is the generic description for P1138 Mini code, but the manufacturer may have a different description for your vehicle model and year. Currently, we have no further information about the P1138 Mini OBDII code.

P1138 NISSAN – Swirl Control Valve Actuator System Performance

P1138 NISSAN Possible Causes

  • Faulty Swirl Control Valve Position Sensor
  • Swirl Control Valve Position Sensor Circuit Open or Shorted
  • Poor Electrical Connection in Swirl Control Valve Position Sensor Circuit
  • Faulty Swirl Control Valve

How to Fix Code P1138 NISSAN?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

When is the Code Detected?

The P1138 code is detected when the target opening angle of the swirl control valve controlled by the Engine Control Module (ECM) and the input signal from the swirl control valve position sensor are not within the normal range.

Possible Symptoms

  • Check Engine Light On (or Service Engine Soon Warning Light)

P1138 NISSAN Meaning

At idle and during low engine coolant temperature, the swirl control valve closes, thus increasing the air speed in the intake passage, promoting fuel vaporization and creating a swirl in the combustion chamber.
Due to this operation, this system tends to increase the combustion speed of the gas mixture, improve fuel consumption, and enhance stability under operating conditions.
Additionally, except at idle and when the engine coolant temperature is low, this system opens the swirl control valve.
Under this condition, this system tends to increase power by improving intake efficiency through the reduction of intake flow resistance and intake flow.
The swirl control valve is actuated by the Engine Control Module (ECM).

P1138 PONTIAC – HO2S Bank 1 Sensor 2 Rich or High Voltage

P1138 PONTIAC Possible Causes

What does this mean?

  • Faulty HO2S, Bank 1 Sensor 2
  • Open or short circuit in Bank 1 Sensor 2 HO2S harness
  • Poor electrical connection in Bank 1 Sensor 2 HO2S circuit

How to fix P1138 PONTIAC code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Check Engine Light on (or service engine soon warning light)

P1138 PONTIAC Meaning

To control emissions, a catalytic converter converts harmful exhaust gas emissions into harmless water vapor and carbon dioxide. The Powertrain Control Module (PCM) can monitor this process using a heated rear oxygen sensor 2 (HO2S 2). The HO2S 2, located in the exhaust stream beyond the catalytic converter, produces an output signal that indicates the catalyst’s storage capacity. This signal indicates the catalyst’s ability to effectively convert exhaust emissions. If the catalyst is working properly, the HO2S 2 signal will be much less active than the signal produced by the front heated oxygen sensor 1 (HO2S 1).

P1138 SATURN – HO2S Bank 1 Sensor 2 Rich or High Voltage

P1138 SATURN Possible Causes

  • Faulty HO2S, Bank 1 Sensor 2
  • Open or short circuit in Bank 1 Sensor 2 HO2S wiring harness
  • Poor electrical connection in Bank 1 Sensor 2 HO2S circuit

How to Fix P1138 SATURN Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Check Engine Light on (or Service Engine Soon warning light)

P1138 SATURN Meaning

To control emissions, a catalytic converter converts harmful exhaust gas emissions into harmless water vapor and carbon dioxide. The Powertrain Control Module (PCM) can monitor this process using a heated rear oxygen sensor 2 (HO2S 2). The HO2S 2, located in the exhaust stream beyond the catalytic converter, produces an output signal that indicates the catalyst’s storage capacity. This signal indicates the catalyst’s ability to effectively convert exhaust emissions. If the catalyst is functioning properly, the HO2S 2 signal will be much less active than the signal produced by the front heated oxygen sensor 1 (HO2S 1).

P1138 SUZUKI – High Voltage in HO2S Circuit During Fuel Cut Sensor 2 Deceleration

1138 SUZUKI Possible Causes

  • Engine vacuum leak
  • Faulty mass air flow (MAF)
  • Faulty HO2S
  • HO2S harness is open or shorted
  • Poor electrical connection in HO2S circuit

How to Fix Suzuki P1138 Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Engine light on (or service engine soon warning light)

P1138 SUZUKI Meaning

HO2S Circuit High Voltage During Deceleration The fuel cut sensor 2 is the generic description for Suzuki code P1138, but the manufacturer may have a different description for your vehicle model and year. Currently, we have no further information about Suzuki OBDII code P1138.

P1138 VOLKSWAGEN – Fuel System B2 Too Lean

P1138 VOLKSWAGEN Possible Causes

  • Intake air leak
  • Faulty O2 sensor
  • Faulty mass air flow (MAF) sensor
  • O2 sensor harness is open or shorted
  • Poor electrical connection in O2 sensor circuit

How to Fix Volkswagen P1138 Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Check engine light on (or service engine soon warning light)

P1138 VOLKSWAGEN Meaning

Fuel System B2 Too Lean is the generic description for Volkswagen P1138 code, but the manufacturer may have a different description for your vehicle model and year. Currently, we have no further information about Volkswagen P1138 OBDII code.

P1139 – Fuel System B2 Too Rich

P1139 Possible Causes

  • Faulty O2 sensor
  • High fuel pressure
  • Faulty mass air flow (MAF) sensor
  • O2 sensor harness is open or shorted
  • Poor electrical connection in O2 sensor circuit

How to Fix Code P1139?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

  • Check engine light on (or service engine soon warning light)

P1139 Meaning

Fuel System Too Rich Bank 2 is the generic description for code P1139, but the manufacturer may have a different description for your vehicle model and year. Currently, we have no further information about OBDII code P1139.

P1139 AUDI Fuel System B2 Too Rich

P1139 AUDI Possible Causes

  • Faulty O2 sensor
  • High fuel pressure
  • Faulty mass air flow (MAF) sensor
  • O2 sensor harness is open or shorted
  • Poor electrical connection in the O2 sensor circuit
 

How to Fix P1139 AUDI Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

 
 

Possible Symptoms

  • Check engine light on (or service engine soon warning light)
 

P1139 AUDI Meaning

Fuel System Too Rich Bank 2 is the generic description for Audi P1139 code, but the manufacturer may have a different description for your model and vehicle year. Currently, we don’t have more information about the Audi P1139 OBDII code.

P1139 BMW – O2 Sensor Heater Circuit High Voltage, Bank 1 Sensor 2

P1139 BMW Possible Causes

  • Faulty HO2S, Bank 1 Sensor 2
  • Open or short circuit in Bank 1 Sensor 2 HO2S wiring harness
  • Poor electrical connection in Bank 1 Sensor 2 HO2S circuit
 

How to Fix BMW P1139 Code?

Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.

 
 

Possible Symptoms

  • Engine light on (or engine service warning light soon)
 

P1139 BMW Meaning

High voltage in O2 sensor heater circuit, Bank 1 Sensor 2 is the generic description for Bmw P1139 code, but the manufacturer may have a different description for your vehicle model and year. Currently, we do not have more information about the P1139 Bmw OBDII code.