P0411 – Secondary Air Injection Incorrect Flow

Description

The secondary air injection system flow is incorrect.

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Symptoms

  • Rough idle
  • Hesitation
  • Poor acceleration
  • Cold start issues
  • Check engine light

Causes

  • Faulty air pump
  • Stuck check valve
  • Vacuum leak
  • Blocked hose
  • Relay failure

Diagnosis

  • Inspect air pump
  • Check valves
  • Inspect hoses
  • Test relay
  • Scan live data

Repair

  • Replace air pump
  • Replace valves
  • Fix vacuum leaks
  • Replace hoses
  • Replace relay

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