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2018 LINCOLN MKX

2.7L EcoBoost V6AWDAUTOMATICgasturbo
5 active safety recalls on this vehicle — view recalls
Repairs0Labor1190Torque9534Fluid15DTC1932Battery0Maintenance0Recalls5
P0411moderate severityPowertrain

Secondary Air Injection System Incorrect Flow Detected

on 2018 Lincoln MKX 2.7L EcoBoost V6 · AWD

What this code means

The secondary air injection system is not providing the expected airflow.

Symptoms

  • Check Engine Light
  • Failed emissions test

Common causes

  • Blocked AIR passages
  • Stuck check valve
  • Weak AIR pump
  • Exhaust leak allowing backflow

Diagnostic steps

  1. Monitor O2 sensor during AIR pump activation (should go lean)
  2. Check AIR pump output
  3. Inspect check valve
  4. Check for blocked passages

Repair notes

Clear blockage or replace AIR pump/check valve.

Other Powertrain codes on this vehicle

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