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1999 JEEP CHEROKEE

4.0L I6AWDAUTOMATICgas
8 active safety recalls on this vehicle — view recalls
Repairs0Labor505Torque2487Fluid9DTC645Battery0Maintenance0Recalls8
P2440moderate severityPowertrain

Secondary Air Injection System Switching Valve Stuck Open Bank 1

on 1999 Jeep Cherokee 4.0L I6 · AWD

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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