P0170moderate severityPowertrain

Fuel Trim Bank 1

on 2003 Mitsubishi Eclipse 3.0L V6 · FWD

What this code means

The fuel trim values for Bank 1 are outside the acceptable range, indicating a persistent lean or rich condition.

Symptoms

  • Check Engine Light
  • Poor fuel economy
  • Rough idle
  • Hesitation

Common causes

  • Vacuum leak
  • Faulty O2 sensor
  • Fuel pressure issue
  • MAF sensor problem
  • Exhaust leak

Diagnostic steps

  1. Check long-term fuel trim values
  2. Inspect for vacuum leaks
  3. Test fuel pressure
  4. Test MAF sensor
  5. Check for exhaust leaks

Repair notes

Diagnose and correct the underlying lean or rich condition.

Other Powertrain codes on this vehicle

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