Back to 2003 BMW 525iT E39

2003 BMW 525IT E39

2.5L I6 M54 TouringRWDAUTOMATICgas
Repairs0Labor595Torque2406Fluid7DTC722Battery0Maintenance0Recalls0
P2440moderate severityPowertrain

Secondary Air Injection System Switching Valve Stuck Open Bank 1

on 2003 BMW 525iT E39 2.5L I6 M54 Touring · RWD

What this code means

The secondary air injection switching valve on bank 1 is stuck in the open position.

Symptoms

  • Check engine light
  • Failed emissions test
  • Noise from air injection system

Common causes

  • Carbon deposits in valve
  • Failed diaphragm
  • Broken valve spring
  • Vacuum supply issue

Diagnostic steps

  1. Inspect valve operation
  2. Check vacuum supply
  3. Listen for air injection noise at idle

Repair notes

Replace secondary air switching valve.

Other Powertrain codes on this vehicle

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