ERROR CODES / OWNER GUIDE
2015 F-150 P0299 Turbo Underboost Code
P0299 is an underboost condition on an equipped EcoBoost engine.
P0299 describes boost pressure below the computer’s expected value. It is relevant to turbocharged EcoBoost engines, but the code alone does not prove either turbocharger has failed.
Confirm which engine is installed and note if the code appears under acceleration, towing or particular temperatures.
Confirm your engine first
The 2015 F-150 offered 2.7L and 3.5L EcoBoost turbocharged V6 engines, as well as naturally aspirated 3.5L V6 and 5.0L V8 engines. Check which one is in the truck before using an internet troubleshooting chart.
What underboost may feel like
A driver may notice reduced acceleration, limited power or a check-engine light, often during a higher-demand situation. Other codes may accompany P0299. Record the load, gear, temperature and whether the truck was towing.
Possible explanations
Charge-air leaks or loose connections, sensor errors and boost-control faults can prevent target pressure from being reached. Internal turbocharger damage is also possible but should be demonstrated through testing rather than assumed.
The next step
A shop can inspect the charge-air path, compare requested versus measured boost and assess related control and sensor data. Continued hard use while the truck is limiting power is unwise, particularly with a trailer.
Next steps
- Confirm 2.7L or 3.5L EcoBoost.
- Save P0299 and other codes with freeze-frame data.
- Record when power loss occurs.
- Request tested evidence before authorizing turbocharger replacement.
Sources and further reading
These are the original manufacturer resources and service documents used to check the technical points above. They may be updated, and vehicle-specific information takes priority.
I own a 2015 Ford F-150 and plan to add real observations, photos and maintenance notes to these guides. I won't present an untested repair as something I've personally done.