Engine-Codes - Generic - P1133

P1133 - HO2S Insufficient Switching Sensor 1

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

P1133 Possible Causes

  • Faulty Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1
  • Vacuum leak
  • Faulty Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 harness is open or shorted
  • Faulty Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 circuit poor electrical connection

How is the P1133 code repair?

Start by checking 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





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What is the cost to diagnose the P1133 code

Labor: 1.0

The cost to diagnose the P1133 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.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P1133 Meaning

The Powertrain Control Module (PCM) monitors the Heated Oxygen Sensor (HO2S) activity for 90 seconds after closed loop operation has begun. The PCM determines if the front HO2S is functioning properly by counting the number of HO2S-1 Lean/Rich (L/R) and Rich/Lean (R/L) switches.

More Information

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