P0243 means Turbocharger/Supercharger Wastegate Solenoid A. The computer has found an electrical fault in the solenoid that controls the turbocharger wastegate, so it cannot regulate boost properly. It is a generic OBD-II code, so the definition is the same on any make, but the most likely cause varies by engine; confirm with a scan tool and the service information for your vehicle before buying parts.
What P0243 means
Modern engines measure boost and fuel rail pressure and compare them with a desired value calculated from engine speed, load and throttle. When actual pressure falls short of desired for long enough, the computer sets a code and often reduces power to protect the engine. Watching desired and actual values side by side on a scan tool shows whether the shortfall is constant or only appears under load.
P0243 symptoms
- Low or no boost
- Overboost on some engines
- Reduced power or limp mode
- Check engine light
Common causes of P0243
- Failed wastegate solenoid
- Wiring or connector fault
- Cracked or disconnected vacuum or boost hoses to the solenoid
How to diagnose P0243
- Check solenoid resistance
- Inspect the solenoid’s hoses
- Command the solenoid with a scan tool and listen for clicking
Can you drive with P0243?
Yes, gently; boost may be limited.
P0243 tips
Cracked rubber hoses between the solenoid, turbo and intake are common on older engines; replace any that are hard or split. Command the solenoid on and off with a scan tool while listening and feeling for a click, then check the hose routing against the diagram on the vehicle or in the service manual.
Will P0243 clear itself?
If the fault stops, the computer turns off the check engine light by itself after several drive cycles without seeing it again, and the code stays in memory as history for a while. Clearing P0243 with a scan tool after a repair is fine, but if the cause is still there the code returns, sometimes within one drive. Disconnecting the battery also clears codes on most vehicles, but it erases learned fuel trims and idle settings as well.
Related codes
| Code | Meaning |
|---|---|
| P0234 | Turbocharger/Supercharger A Overboost Condition |
| P0299 | Turbocharger/Supercharger A Underboost Condition |
| P0236 | Turbocharger/Supercharger Boost Sensor A Circuit Range/Performance |
Guides that help
When it is more than a sensor
Our superchargers page lists supercharger kits, and diesel owners can read the 6.7 Cummins turbo guide. If a failed turbo or fuel pump has damaged the engine, compare engines by code on our engines page.
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