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17544/P1136/004406 - Fuel Trim: Bank 1 (Add): System too Lean
- Check Mass Air Flow (MAF) Sensor
- Check Fuel Pressure Regulator
- Check Fuel Pump
- Check Intake/Exhaust System for Leaks
- Check Secondary Air Injection for Leaks
- Check Vacuum Lines for Leaks
- Fuel Trim Info
- When this fault is stored and external vacuum leaks are not found, less obvious problems may be present:
- Check Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80)
- Check Brake Booster and Hoses
- Check Electric Vacuum Pump ( If Applicable )
- Check Crankcase Ventilation System for faulty components. When the PCV or Crankcase Ventilation System is faulty, vacuum is typically present under the oil cap and misfire faults are common.
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