Mazda DTC P1143 – HO2S Bank 1 Sensor 3 Signal Below 0.45v (A/F Ratio Too Lean)
DTC P1143 meaning on Mazda
- DTC: P1143
- HO2S: Heated Oxygen Sensor
- Bank 1 Sensor 3: Refers to the specific oxygen sensor location in the exhaust system
- Signal Below 0.45v: Indicates that the oxygen sensor signal voltage is lower than expected
- A/F Ratio Too Lean: Indicates that the air-fuel mixture is leaner than optimal
Mazda DTC P1143 symptoms
- Check Engine Light (MIL) illuminated
- Poor fuel economy
- Rough idling or engine stalling
- Lack of power during acceleration
Mazda DTC P1143 causes
- Faulty oxygen sensor (Bank 1 Sensor 3)
- Vacuum leaks in the intake system
- Fuel delivery issues
- Exhaust system leaks
- Issues with the engine’s air intake system
Mazda DTC P1143 seriousness
The DTC P1143 code should not be ignored as it can lead to poor engine performance, reduced fuel efficiency, and potential damage to the catalytic converter over time.
How to diagnose DTC P1143 on Mazda
- Use an OBD-II scanner to retrieve the specific trouble code
- Inspect the oxygen sensor (Bank 1 Sensor 3) for any visible damage or contamination
- Check for vacuum leaks in the intake system
- Verify fuel pressure and delivery system functionality
- Inspect the exhaust system for leaks
How to fix DTC P1143 on Mazda
- Replace the faulty oxygen sensor (Bank 1 Sensor 3)
- Repair any vacuum leaks in the intake system
- Address fuel delivery issues if present
- Fix any exhaust system leaks
- Clean or replace the air filter if necessary
How to erase DTC P1143 on Mazda
After fixing the underlying issue causing the DTC P1143 code, you can use an OBD-II scanner to clear the code and reset the Check Engine Light.
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