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
P0234The turbo is giving more boost than allowedUrgency medium
Turbocharger/Supercharger "A" Overboost 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 clearly exceeds what the engine computer asks for.
What the car has detected
The measured boost pressure has exceeded the target by more than the allowed margin for over a second.
Drive gently and have it checked soon: too much boost puts more stress on the engine than intended and the engine computer may limit power to protect it.
Symptoms
- Engine warning light on
- Surging or a brief burst of extra power
- Loss of power or limp mode when the engine computer limits it
- Uneven running when accelerating
Possible causes
- Wastegate that won't open or is seized
- Faulty or stuck turbo control valve
- Vacuum or control lines misconnected, loose or blocked
- Boost pressure sensor reading wrong
- Seized turbo or turbo vanes
Checks for the garage
- Read the freeze frame data and compare actual with requested boost
- At rest, check the boost sensor reads the same as atmospheric pressure
- Check the vacuum and control lines are properly connected and unblocked
- Activate the control valve with diagnostics and check the wastegate moves and opens
- Check the turbo if everything above is fine
Next step
Avoid full throttle and have the wastegate, the turbo control valve and the pressure sensor checked.
Go to a garage soon; don't push the engine until it has been checked. Checking turbo regulation needs diagnostics.
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.