P1143
Heated Oxygen Sensor 1 Lean Shift Monitoring Bank 1
P1143 is an OBD-II diagnostic trouble code meaning: Heated Oxygen Sensor 1 Lean Shift Monitoring Bank 1. Common causes: air leak in the intake tract, malfunction of the mass air flow sensor (maf). Estimated repair cost: $17–89.
Symptoms
- Increased fuel consumption
- Reduced engine power
- Unstable engine idling
- Check Engine Light Is On
- Dips during acceleration
Causes
- Air leak in the intake tract
- Malfunction of the mass air flow sensor (MAF)
- Dirty or faulty oxygen sensor
- Problems with the fuel pump or injectors
- Vacuum system leaking
How to Fix
- Check the intake tract for air leaks
- Check the serviceability of the mass air flow sensor and clean or replace if necessary
- Check the condition of the oxygen sensor and its wiring
- Check fuel pressure and condition of fuel injectors
- Check vacuum hoses for leaks
Related codes
Error P1143 by Vehicle Brand
FAQ
What does the P1143 code mean?
P1143 is an OBD-II diagnostic trouble code that indicates: Heated Oxygen Sensor 1 Lean Shift Monitoring Bank 1
What causes a P1143 error code?
The most common causes of P1143 include: Air leak in the intake tract; Malfunction of the mass air flow sensor (MAF); Dirty or faulty oxygen sensor; Problems with the fuel pump or injectors.
How do I fix a P1143 diagnostic trouble code?
To fix P1143: Check the intake tract for air leaks. Check the serviceability of the mass air flow sensor and clean or replace if necessary. Check the condition of the oxygen sensor and its wiring. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with P1143?
Yes, but get it checked soon
How much does it cost to fix P1143?
The estimated repair cost for P1143 is $17–89. Actual cost depends on your vehicle, location, and labor rates.
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