Engine
Turbo Wastegate
The wastegate controls turbo boost by diverting exhaust gas away from the turbine.
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Combustion flow
Interactive — tap a partTap a part to see how it fits in the system.
What it does
- Regulates maximum boost pressure
- Diverts exhaust gas past the turbine
- Electronic or actuator controlled
When it fails
- Loss of boost / power
- P0299 underboost code
- P0234 overboost code
- Boost spikes
How to diagnose
- Test the actuator with a vacuum/pressure pump
- Check the linkage for sticking
- Test the boost solenoid
- Read boost pressure live
Maintenance
- Keep the actuator linkage clean and free
- Replace worn actuators and solenoids
Use the diagnosis order. When a part fails, confirm each hypothesis with measurements before replacing anything — codes and symptoms overlap.
Related part
Turbocharger
A turbocharger uses exhaust gas to force more air into the engine for more power.