P0299 on Acura: How to Diagnose & Fix
Turbo/Supercharger Underboost Condition
1 Acura model · 1 documented issue · $400-$2,200 repair
P0299 on Acura by model: symptoms, diagnosis and fix
The first-generation RDX's K23A1 2.3L turbocharged four is unique in the Honda/Acura lineup, and its most commonly reported hard failure is not the turbo cartridge itself but the variable-flow wastegate actuator that controls it. The rubber diaphragm inside the flow actuator tears with age and heat cycling (owners commonly report this in the 90,000-130,000 mile range), so the actuator can no longer hold or modulate the wastegate arm. The result is underboost or overboost codes, a check engine light, and reduced power. Owners on AcuraZine repeatedly report dealers quoting a complete turbocharger assembly replacement (quotes as high as several thousand dollars) for what is usually an actuator, solenoid, vacuum-line or linkage fault. The vacuum lines, boost control solenoid, wiring and wastegate linkage are all more likely to fail on this engine than the turbo bearings.
Common Symptoms
- Check engine light with boost-related codes
- Noticeable loss of power / feels non-turbo
- Limp mode under acceleration
- Hissing or vacuum leak sound from engine bay
- Boost gauge or scan-tool boost lower than spec
How to Fix
Diagnose before condemning the turbo: smoke- or vacuum-test the flow actuator diaphragm, inspect all boost-control vacuum lines for cracking and the wastegate arm for seized/worn linkage, and test the boost control solenoid. In most documented cases replacing the flow actuator (and solenoid/vacuum lines as needed) restores normal boost at a fraction of the turbo-assembly quote. There is no recall or warranty extension for this failure. Full turbo replacement is only warranted if there is shaft play, exhaust-side damage, or oil-seal failure.
Sources for this issue (3)
P0299 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0299 mean on a Acura?
P0299 stands for "Turbo/Supercharger Underboost Condition." P0299 means the engine computer detected an underboost condition — the turbocharger or supercharger is producing less boost pressure than the PCM expects for the given conditions. The computer compares the manifold/boost pressure sensor reading to a target based on engine load, and when actual boost falls short, it sets this code. The most common real-world cause is a leak somewhere in the intake/charge-air path. You'll typically feel reduced power or sluggish acceleration, and the engine may go into a reduced-power mode. On Acura it is documented across 1 model: RDX.
What are the most common causes of P0299?
The most common causes of P0299 are: Boost/intake leak (cracked or loose charge-air hose or intercooler), Faulty or sticking turbo wastegate or actuator, Stuck or clogged variable-geometry turbo vanes (VGT), Faulty boost pressure or MAP sensor, Leaking or disconnected vacuum/boost control lines, Restricted air intake or clogged air filter, Failed boost control solenoid, Worn or failing turbocharger. The specific cause varies by vehicle.
How much does it cost to fix P0299 on a Acura?
Published repair estimates on Acura range from $400 to $2,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0299 on a different make?
View P0299 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.