[SOLVED] P1158 Code: Rich Fuel Mixture – Fixing Heated Oxygen Sensor Switches

If you see the engine light on or the service engine soon warning light, it could be due to the automobile fault code P1158. This code is typically caused by exhaust gas leaks, a faulty heated oxygen sensor 2 (HO2S2) downstream in bank 2, an open or shorted harness for the heated oxygen sensor 2 in bank 2, poor electrical connection in the circuit, inappropriate fuel pressure, or faulty fuel injectors.

To fix this issue, you should visually inspect the wiring harness and connectors, checking for any damage or broken pins. The repair time for this code is estimated to be around 1.0.

Make sure to check the possible causes mentioned above to accurately interpret the fault code.

Repair Importance Level10.0 (Out of 10)
Estimated Repair TimeApproximately 1.0 hour
Repair Difficulty Level6.67 (Out of 10)

When the engine light is on or the service engine soon warning light is illuminated, it could be a sign of the p1158 fault code.

  • The symptoms of the automobile fault code P1158 include the Engine Light being ON or the Service Engine Soon Warning Light being illuminated.

The automobile fault code p1158 can be caused by exhaust gas leaks, faulty Heated Oxygen Sensor 2 (HO2S2) (Downstream) Bank 2, open or shorted harness, poor electrical connection, inappropriate fuel pressure, or faulty fuel injectors.

  • The fault code P1158 can be caused by various factors, including exhaust gas leaks, a faulty Heated Oxygen Sensor 2 (HO2S2) (Downstream) in Bank 2, an open or shorted harness for Heated Oxygen Sensor 2 in Bank 2, a poor electrical connection in the circuit of Heated Oxygen Sensor 2 in Bank 2, inappropriate fuel pressure, and faulty fuel injectors.

To fix the p1158 fault code, start by visually inspecting the wiring harness, connectors, and components for any damage or corrosion.

  • To fix the automobile fault code p1158, first, check the possible causes mentioned above.
  • Then, visually inspect the wiring harness and connectors related to the issue.
  • Look for any damaged components and check if there are any broken, bent, pushed out, or corroded pins in the connectors.
  • This fix is estimated to take approximately 1.0 hour.

The factors influencing the diagnosis and fixing cost of the automobile fault code p1158 are the estimated repair time and the hourly rate charged by auto repair shops. The estimated repair time for this fault code is 1.0 hour.

Auto repair shops typically charge between $75 and $150 per hour for their services.

These factors will determine the overall cost of diagnosing and fixing the p1158 fault code.

The P1158 fault code refers to a lack of heated oxygen sensor switches in Bank 2 Sensor 2, indicating a rich air-fuel mixture. The Heated Oxygen Sensor 2 (HO2S2) is located downstream of the three-way catalyst and monitors the oxygen level in the exhaust gas on each bank of the engine.

It is crucial for the catalyst’s optimal operation that the air-fuel mixture maintains a near stoichiometric ratio. The PCM (Powertrain Control Module) adjusts the fuel injection time to achieve this ratio based on the HO2S2’s output voltage. When the oxygen in the exhaust gas decreases, the air-fuel ratio becomes rich, and the PCM interprets this as a voltage above 0.45 V from the HO2S2. The P1158 code is triggered when the PCM detects that the HO2S2 signal remains above the voltage range for an extended period. This fault code indicates that there is a problem with the heated oxygen sensor switches in Bank 2 Sensor 2, leading to a consistently rich air-fuel mixture.

It is important to address this issue promptly to ensure proper engine performance and reduce emissions.

How can I determine if the engine light is on due to a fault code p1158?

If your engine light is on and you suspect it’s due to fault code P1158, there are a few things you can do to determine the cause. Start by checking for exhaust gas leaks and inspecting the Heated Oxygen Sensor 2 (HO2S2) downstream of Bank 2. Make sure the wiring harness and connectors are in good condition, and look for any damaged components or corroded pins. Additionally, check the fuel pressure and the condition of the fuel injectors. By following these steps, you can pinpoint the cause of the engine light and take the necessary steps to fix it.

What are the possible causes of fault code p1158 in an automobile?

If you’re seeing the engine light on or the service engine soon warning light in your automobile, it could be due to fault code P1158. This code can be caused by a few different things, including exhaust gas leaks, a faulty heated oxygen sensor 2 (HO2S2) downstream in bank 2, an open or shorted harness for the heated oxygen sensor 2 in bank 2, a poor electrical connection in the circuit, inappropriate fuel pressure, or faulty fuel injectors. To fix this issue, start by visually inspecting the wiring harness and connectors, checking for any damage or broken pins.

What steps should I take to fix fault code p1158 in my vehicle?

If you’re dealing with fault code p1158 in your vehicle, there are a few steps you can take to fix it. Start by checking the possible causes, which include exhaust gas leaks, a faulty Heated Oxygen Sensor 2 (HO2S2) (Downstream) Bank 2, an open or shorted harness for Heated Oxygen Sensor 2 Bank 2, a poor electrical connection in the Heated Oxygen Sensor 2 Bank 2 circuit, inappropriate fuel pressure, or faulty fuel injectors. Next, visually inspect the related wiring harness and connectors, looking for any damage or broken, bent, pushed out, or corroded pins. This will help you identify and address the issue.

p1158 error fault code explained

If your engine light is on and you’re seeing the P1158 fault code, it could be due to exhaust gas leaks, a faulty Heated Oxygen Sensor 2 (HO2S2) (Downstream) Bank 2, an open or shorted harness, poor electrical connection, inappropriate fuel pressure, or faulty fuel injectors. To fix it, visually inspect the wiring harness and connectors, check for damaged components, and look for broken, bent, pushed out, or corroded connector pins.

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