OBD Guide

P0173

Fuel Trim Bank 2

Severity: MEDIUM

Symptoms

  • Increased fuel consumption
  • Unstable idle
  • Reduced engine power
  • Smell of gasoline from the exhaust pipe

Causes

  • Dirty/defective fuel injectors
  • Vacuum leaks in bank 2
  • Malfunction of the mass air flow sensor (MAF)
  • Problems with oxygen sensors
  • Dirty air filter
  • Malfunction of the fuel pump or pressure regulator
  • Leaks in the intake system

How to Fix

  1. Check the system for vacuum leaks (especially bank 2)
  2. Clean or replace the mass air flow sensor
  3. Check oxygen sensor readings
  4. Clean or replace fuel injectors
  5. Check fuel pressure and pump performance
  6. Clean throttle body

Related codes