P0299 signifies a "Turbocharger/Supercharger
P0299 The OBD-II code P0299 signifies a "Turbocharger/Supercharger A Underboost Condition," meaning the turbocharger isn't producing enough boost pressure for the engine. This is often caused by a leak in the boost system, a faulty turbocharger or actuator, a restricted air filter or diesel particulate filter, or a bad boost pressure sensor. Symptoms include loss of engine power and an illuminated check engine light. This video explains how to diagnose and fix a P0299 code: Common causes of P0299 • Boost leaks: Leaks anywhere in the plumbing of the turbo system, including hoses, intercoolers, and clamps, can cause low boost pressure. • Faulty turbocharger or actuator: The turbocharger itself or its control components, like the wastegate or actuator diaphragm, can fail and fail to produce adequate pressure. • Restricted air intake or exhaust: A clogged air filter or a blocked diesel particulate filter (DPF) can restrict the flow of air into the engine, leading to underboost. • Faulty sensor: A malfunctioning boost pressure sensor or other related sensors can incorrectly report low boost to the engine's computer, triggering the code. • EGR system fault: A problem with the Exhaust Gas Recirculation (EGR) system can also lead to an underboost condition. Symptoms of P0299 • Illuminated check engine light (Malfunction Indicator Lamp) • Reduced engine power and performance, especially under acceleration • The vehicle may enter "limp mode," which limits engine power to prevent further damage How to diagnose and fix • Do not assume the turbo is bad: Many issues can cause a P0299 code, and replacing the turbo is often unnecessary. A complete diagnosis is crucial. • Check for leaks: Inspect all boost hoses, clamps, and the intercooler for any signs of leaks or damage. • Check sensors: Inspect the boost pressure sensor and its hoses for blockages, damage, or incorrect readings. • Check exhaust and intake: Inspect the air filter for restriction and, if applicable, the DPF for blockages. • Inspect the turbocharger's control system: Check the turbocharger's wastegate or actuator for proper movement and to see if the diaphragm has failed. • Consider other components: A faulty PCV valve or other control valves can also trigger this code. This video shows how to inspect the turbocharger wastegate and actuator for P0299:
