How to fix P0299 Code: Turbo / Supercharger Underboost Condition
The boost is the amount of positive pressure that is being created by the turbocharger.
When the pressure is low, an underboost condition will exist, which the computer (ECM/PCM) will receive through sensors and send out a P0299 code.
The computer calculates the parameters with data from sensors such as the mass airflow sensor, ambient air temperature, and manifold absolute pressure sensor
The computer will consider variations but there is a threshold of pressure needed or the computer will send out a P0299 code.

Possible Causes of a P0299 Code
Intake Air Restriction (Dirty Air Filter)
Bad Waste Gate
Bad Hose Connections
Air intake leak
Faulty sensor (BARO/MAP/Boost Pressure Sensor)
Faulty intercooler

By using this information user assumes all risk of use.
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