OBD2 codes.
A code identifies a signal or system that needs to be checked, not a part you should replace.
Got an OBD2 Bluetooth adapter? Read the codes straight from your car.1 code entry · 1 related fault
P0299The turbo is giving less boost than neededUrgency medium
Turbocharger/Supercharger "A" Underboost Condition
The turbocharger compresses the air going into the engine to give it more power; the engine computer regulates that boost pressure with the wastegate or the turbo's vanes. This code means the actual pressure stays clearly below what the engine computer asks for.
What the car has detected
When power was demanded for several seconds, the measured boost pressure stayed below the target by more than allowed.
You can drive carefully, but the car lacks power and may go into limp mode. If there is also blue smoke or the turbo makes noises, stop and have it checked: it could be damaged.
Symptoms
- Engine warning light on
- Lack of power, especially when accelerating
- Limp mode with limited power
- Whistling or hissing from a pressurised air leak
- Higher fuel consumption
Possible causes
- Boost leaks: split hoses, loose clamps or a leaking intercooler
- Seized wastegate or wastegate linkage
- Faulty turbo control valve or its vacuum lines
- Blocked intake or exhaust, for example a clogged catalytic converter or particulate filter
- Boost pressure sensor reading wrong
- Worn or damaged turbocharger
Checks for the garage
- Read the freeze frame data and compare actual with requested boost
- With the engine off and ignition on, check the boost sensor reads the same as atmospheric pressure
- Check the whole intake path, intercooler, hoses, clamps and vacuum lines
- Activate the turbo control valve with diagnostics and see whether the wastegate really moves
- Check that the exhaust is not blocked
- Check the turbo and its oil supply last
Next step
Check that the turbo and intercooler hoses are not loose or split, and have the wastegate and pressure sensor checked.
Go to a garage if you can't see an obvious leak or if the car goes into limp mode. If the turbo is noisy or there is blue smoke, don't push it and go as soon as possible.
Original sources · Date indicated: 2026-10-12
Related faults in the database
Lack of power with the engine warning light and P0299 / P0234 on the 1.6 EcoBoost: wastegate solenoidInjection / turbo
- Engine / equipment
- 1.6 EcoBoost direct injection: Focus, C-Max, Kuga, Fiesta ST, Mondeo and Transit Connect
- Period mentioned
- 2013–2016
- Symptoms
- The engine loses power and the engine warning light comes on. The computer stores codes P0234 (turbo overboost), P0245 or P0246 (wastegate solenoid circuit) or P0299 (turbo underboost).
- Possible cause described
- Ford bulletin 15-0162 (October 2015) for the 1.6 EcoBoost of the Escape, Fiesta ST and Fusion says to check the charge-air-cooler pipes and vacuum lines first; if they are fine, the cause is the solenoid valve that regulates the turbo wastegate, and it is replaced.
- Check for the garage
- Read the codes. Check that the charge-air-cooler pipes and vacuum lines are not split or loose; if they are fine, test the wastegate solenoid (under the engine) and make sure its hoses are fully fitted before replacing the turbo.
- Cost cited in the source
- No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.