Reference meaning
What does this code mean?
The monitored boost is insufficient for the calibrated operating condition. This describes a control result, not proof of a failed turbocharger. Air-path restriction, control-system behavior and environmental conditions must be evaluated within the vehicle procedure. The cited GM bulletin documents an ice-related case with possible reduced power.
Sources and interpretation [1] [3]
A code identifies a detected condition, not a part that must automatically be replaced.
Narrow by vehicle
A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Manufacturer example · limited applicability
GM 22-NA-002 covers 2018–2022 Equinox/Terrain 1.5L LYX in the US/Canada and links cold-weather codes to moisture/ice and boost control. Its first-page list labels P0234 as underboost; that conflicts with the Ford/Audi overboost definition. We use it for the scoped cold-weather example, not to redefine P0234.
Before replacing a part
Record whether the fault occurs only in cold weather and compare desired with actual boost. Review the exact engine's air path and boost-control tests. A cold-weather bulletin is not evidence that every P0299 requires a turbocharger or software replacement.
Scan worksheet →Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P0299-00Turbocharger Underboost
P0299Negative Pressure Deviation
P0299-00Turbocharger Underboost Condition
Manufacturer communications
285Original wording in English
AUDI
This Pending Service Solution (PSS) requests that technicians create a record in the PSS database when there is an exhaust emissions warning lamp illuminated, DTC P0299 sumptom 34203; V6 TFSI.
AUDI
This Pending Service Solution (PSS) requests that technicians create a record in the PSS database when there is an exhaust emissions warning lamp illuminated, DTC P0299 sumptom 34203; V6 TFSI.
AUDI
This Pending Service Solution (PSS) requests that technicians create a record in the PSS database when there is an exhaust emissions warning lamp illuminated, DTC P0299 sumptom 34203; V6 TFSI.
BUICK, CHEVROLET, GMC
This document assists dealer technician's with diagnosing a MIL P0299.
Check vehicle applicability
800A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Sources and interpretation
These explanations are editorial summaries of the linked manufacturer material. PDF page numbers count from the first file page. Original publications are in English; translations are reference aids. A cited edition is not a claim that it is the manufacturer's latest instruction.
- Audi TT Quick Reference Specification Book · October 2013 ↗
Audi of America · PDF page(s) 137 · 2013-10
- 22-NA-002 · P0299/P0234 during cold or freezing temperatures ↗
General Motors · PDF page(s) 1 · 2022-02
- 2024–2025 MY OBD System Operation Summary for Gasoline Engines ↗
Ford Motor Company · PDF page(s) 86, 87 · 2024-04-16
Source check date · 2026-10-27
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.