DTC P0299: Turbocharger/Supercharger A UNDERBOOST Condition

WARNING: This page does not describe the selected car, but rather 33 other vehicles, including the 2010 Mercury Mountaineer, 2010 Mercury Milan, 2010 Mercury Mariner, 2010 Mercury Grand Marquis, and 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0299: TURBOCHARGER/SUPERCHARGER A UNDERBOOST CONDITION

Description:	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. The DTC 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 TC wastegate regulating solenoid valve stuck Wastegate stuck open Wastegate control hose open or plugged Air leak between turbocharger and throttle
Diagnostic Aids:	Check tubing for obstructions, cracks and poor fitting connections. Check the TC wastegate regulating solenoid valve for proper operation.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST HN .