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2020 GMC ACADIA
2.5L I4•AWD•AUTOMATIC•gas
6 active safety recalls on this vehicle — view recalls
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Repairs0Labor483Torque4233Fluid9DTC1253Battery1Maintenance0Recalls6
P1190moderate severityPowertrain

Engine Vacuum Leak

on 2020 GMC Acadia 2.5L I4 · AWD

What this code means

The PCM detected an engine vacuum leak based on fuel trim adaptation data. The system has determined that unmetered air is entering the engine.

Symptoms

  • Check Engine Light
  • Rough idle
  • Lean running condition
  • Poor fuel economy
  • Hissing noise from engine

Common causes

  • Cracked or disconnected vacuum hose
  • Intake manifold gasket leak
  • Brake booster vacuum leak
  • PCV valve or hose leak
  • Throttle body gasket leak

Diagnostic steps

  1. Perform smoke test on intake system
  2. Inspect all vacuum hoses and connections
  3. Check intake manifold gaskets
  4. Test brake booster vacuum hose
  5. Inspect PCV system

Repair notes

Perform smoke test to locate leak. Repair or replace damaged hoses, gaskets, or fittings.

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