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2018 HONDA CIVIC
1.5L I4 Turbo•FWD•CVT•gas•turbo
6 active safety recalls on this vehicle — view recalls
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Repairs403Labor503Torque3385Fluid7DTC1924Battery1Maintenance0Recalls6
P0299moderate severityPowertrain

Turbocharger/Supercharger Underboost Condition

on 2018 Honda Civic 1.5L I4 Turbo · FWD

What this code means

The PCM detected that boost pressure is lower than commanded. This often results from a boost leak, faulty wastegate, or turbo problem.

Symptoms

  • Loss of power
  • Poor acceleration
  • Check engine light

Common causes

  • Boost/vacuum leak
  • Faulty wastegate or actuator
  • Failing turbocharger
  • Faulty boost pressure sensor

Diagnostic steps

  1. Inspect intake and boost hoses for leaks
  2. Check wastegate and actuator operation
  3. Test boost pressure sensor
  4. Inspect turbocharger condition
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