P1133 BMW Possible Causes
What does it mean?
- 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 to Fix BMW P1133 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)
P1133 BMW Meaning
The Powertrain Control Module (PCM) monitors the Heated Oxygen Sensor (HO2S) activity for 90 seconds after closed loop operation begins. The PCM determines if the front HO2S is operating correctly by counting the number of HO2S-1 Lean/Rich (L/R) and Rich/Lean (R/L) switches.