P0299 Code: Turbocharger / Supercharger “A” Underboost Condition

The powertrain control module (PCM) may trigger the check engine light and log an engine trouble code once it detects an issue with your engine’s turbo/supercharger. One possible error that may be set in your vehicle’s on-board diagnostic (OBD) system is the P0299 code.

What Does the P0299 Code Mean?

Diagnostic Trouble Code (DTC) P0299 stands for “Turbocharger/Supercharger “A” Underboost Condition.” It is a generic trouble code related to an engine underboost condition. It may be set once the PCM perceives that the bank “A” single turbocharger or supercharger is producing boost pressure levels in the intake manifold below the manufacturer-specified limit.

The engine usually relies on the downward movement of the pistons to create the vacuum needed to draw air and fuel charge into the engine. A turbo/supercharged engine uses a forced-induction device to draw additional air into the engine.

Turbochargers and superchargers are designed to produce additional pressure (greater than atmospheric pressure) in the intake manifold. This makes it possible for smaller engines to produce power that’s normally seen only in larger engines.

There are several factors that can cause engine underboost, and it may differ per vehicle manufacturer. For instance, code P0299 is usually logged on Ford vehicles once the PCM perceives that the actual throttle intake pressure is less than the desired intake pressure for a given amount of time.

For more information that can help you resolve P0299 especially if you’re planning a DIY fix, you can read our advanced technical discussion about turbochargers and superchargers.

Note: The definition of code P0299 may be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Possible Causes of the P0299 Code?

Here are the common triggers of this error code:

• Intake air restriction or leak
• Malfunctioning turbo/supercharger
• Faulty boost pressure sensor
• Wastegate stuck open
• Air intake leak
• Faulty BARO/MAP sensor
• Restricted intercooler
• Circuit issues, such as damaged wires or poor connections
• An issue with the PCM, such as software in need of an update

There can be other triggers of the code depending on the specific vehicle that you own.

What are the Common Symptoms of a P0299 Code?

Here are some of the common symptoms related to the code:

• Illuminated check engine light
• Lack of engine power
• Noticeable sounds from the engine/turbo

How to Diagnose the P0299 Code

There are many possible triggers of the P0299 code. Given that these triggers vary per manufacturer, it may be hard to identify the component causing the issue. If you’re not an experienced DIYer, it would be best to take your vehicle to an auto repair shop and leave the job to a mechanic.

However, if you prefer to diagnose this code yourself, we recommend consulting vehicle-specific repair manuals or online repair databases. These resources provide helpful information on how to diagnose vehicle issues, such as an underboost condition.

How to Fix the P0299 Code

Fixing a P0299 code isn’t easy. Although it is a generic code, repair steps may vary depending on the vehicle that you own. For instance, repair steps for a P0299 on an Audi may not work for a P0299 code on a Ford.

If you’re not equipped with the skills and tools to get the job done, take your vehicle to an auto repair shop. A mechanic would know how to clear a P0299 code. We also recommend consulting a vehicle-specific repair manual or online repair database to help you find the repair procedures that may work for your vehicle.

Fix a P0299 Code With a New Turbo or MAP Sensor

The P0299 code is stored because the vehicle’s sensors detect that the turbocharger isn’t creating enough boost pressure. Either a turbocharger or the sensor itself could be faulty. If these problems aren’t properly addressed, your vehicle is going to continue to have engine performance issues. Good thing you can get the right replacement parts for your vehicle in just a few clicks here at CarParts.com.

Whether you need a turbocharger or MAP sensor, you can be confident that CarParts.com has a great selection. We only choose parts that can fit properly and perform reliably. We also source parts from reputable manufacturers to ensure that they’ve passed stringent quality control standards.

Reliability is important when it comes to engine components. Rest assured that you’re getting the best when you shop for a new MAP sensor and turbocharger here at CarParts.com!

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