P0299 Fault Code

P0299 OBD-II Trouble Code Short Description

Turbocharger/Supercharger A Underboost Condition

What does trouble code P0299 mean?

The P0299 fault code refers to a turbocharger or supercharger underboost condition in a vehicle. This means that the pressure or boost level from the turbocharger or supercharger is lower than the expected or required level.

This underboost condition can be caused by several factors. It could be due to a leak or restriction in the intake or exhaust system, such as a cracked or disconnected hose, clogged air filter, or a malfunctioning wastegate. It can also be caused by a faulty or worn-out turbocharger/supercharger, or a problem with the engine control module (ECM).

To diagnose and resolve the P0299 fault code, a few steps can be taken:

  1. Check for any visible signs of leaks or damage to the intake or exhaust system. Repair or replace any faulty components.

  2. Inspect the air filter and replace it if it is dirty or clogged.

  3. Test the wastegate operation to ensure it is functioning correctly. If it is not, repair or replace it as necessary.

  4. If no visible issues are found, it may be necessary to perform further diagnostic tests, such as checking the boost pressure sensor, the turbocharger/supercharger, or the ECM.

In some cases, a software update or reprogramming of the ECM might be required to resolve the underboost condition.

It is recommended to consult a qualified mechanic or bring the vehicle to a reputable service center to accurately diagnose and repair the cause of the underboost condition.

Remember, driving with a P0299 fault code can lead to reduced engine performance and potentially, further damage to the turbocharger or supercharger system.


What are the symptoms of the P0299 code?

The P0299 fault code indicates a potential problem with the turbocharger or supercharger system, specifically an underboost condition. Some common symptoms associated with this fault code include:

  • Reduced engine power and acceleration
  • Sluggish or slow response when accelerating
  • Loss of turbocharger or supercharger boost pressure
  • Whistling or hissing noise from the turbocharger or supercharger system
  • Illumination of the check engine light
  • Decreased fuel efficiency

Please note that these symptoms may vary depending on the specific vehicle make and model. It is recommended to consult with a qualified mechanic or use a diagnostic tool to accurately diagnose and resolve the issue.


What causes the P0299 code?

P0299 is a fault code related to a turbocharger or supercharger underboost condition. This indicates that the pressure in the intake manifold is lower than expected, resulting in reduced engine power and performance.

There are several possible causes for this fault code, including:

  1. Boost pressure leak: Any kind of air leak in the system, such as a cracked or disconnected hose, can cause a decrease in boost pressure.

  2. Faulty wastegate: The wastegate controls the flow of exhaust gases to the turbocharger. If it is stuck open or not functioning properly, it can lead to underboost conditions.

  3. Blocked or restricted air intake: A clogged air filter or blocked intake system can limit the amount of air entering the engine, causing reduced boost pressure.

  4. Malfunctioning turbocharger/supercharger: If the turbocharger or supercharger itself is faulty, it may not be able to produce the desired boost pressure.

  5. Vane position sensor malfunction: Most modern turbochargers are equipped with variable geometry vanes to control boost pressure. If the vane position sensor is not working correctly, it can cause an underboost condition.

To diagnose and resolve the P0299 fault code, it is recommended to:

  1. Inspect the intake system for any leaks or blockages.

  2. Check the wastegate and ensure it is functioning properly.

  3. Clean or replace the air filter if necessary.

  4. Inspect the turbocharger/supercharger for any signs of damage or malfunction.

  5. Scan the vehicle's computer system to check for any additional fault codes or diagnostic information.

It is recommended to consult a professional mechanic or dealership for a thorough diagnosis and repair of the P0299 fault code, as it may require specialized knowledge and equipment.

Possible Solutions

How to fix P0299?

To fix the P0299 fault code, which indicates a turbocharger or supercharger underboost condition, you can try the following steps:

  1. Check for any loose or damaged hoses connected to the turbocharger or supercharger system. Repair or replace them if necessary.

  2. Inspect the intercooler for any leaks or blockages. Clean or repair it as needed.

  3. Verify that the wastegate or bypass valve is functioning properly. Make sure it is not stuck or restricted.

  4. Check the air intake system for any obstructions or restrictions. Clean or replace the air filter and clear any debris.

  5. Inspect the turbocharger or supercharger for any damage or wear. Repair or replace it if necessary.

  6. Reset the fault code and test drive the vehicle to see if the underboost condition persists. If it does, further diagnosis may be required.

Please note that these steps are general recommendations, and it is recommended to consult a professional mechanic or refer to the specific vehicle's repair manual for accurate diagnosis and repair procedures.