Diagnostic Trouble Code – P0299


P0299 – Turbocharger/Supercharger Underboost

The Powertrain Control Module (PCM) continuously monitors the turbocharger system for an underboost condition. The PCM checks for a minimum Throttle Intake Pressure (TIP) Parameter Identification (PID) reading during engine operation, which indicates an underboost condition. Code P0299 turbo underboost sets when the PCM detects that the actual throttle intake pressure is less than the desired throttle intake pressure by 27.6 kPa (4 psi) or more for 5 seconds.

Possible Causes

  • Damaged turbocharger (TC) wastegate regulating valve solenoid
  • Stuck TC wastegate regulating solenoid valve
  • Wastegate stuck open
  • Wastegate control hose open or plugged
  • Air leak between turbocharger and throttle
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