P0510 means Closed Throttle Position Switch. The computer is not seeing the expected closed-throttle (idle) signal, so it may not recognize when the throttle is shut. 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 P0510 means
Most vehicles built in the last two decades use electronic throttle control instead of a throttle cable: the accelerator pedal carries two or three position sensors, and the throttle body has a motor and two position sensors of its own. The computer compares the redundant sensors constantly, and any disagreement triggers reduced-power mode as a safety measure. Older engines with a throttle cable control idle with a separate idle air control valve.
P0510 symptoms
- High or unstable idle
- Stalling
- Hesitation off idle
Common causes of P0510
- Misadjusted or failed throttle switch or sensor
- Sticking throttle plate
- Idle position not learned after service
How to diagnose P0510
- Check that the throttle closes fully
- Watch the closed-throttle signal on a scan tool
- Perform an idle relearn if required
Can you drive with P0510?
Usually yes.
P0510 tips
On older vehicles with an adjustable throttle switch, set it to specification with the throttle fully closed. On vehicles with electronic throttle, this signal comes from the throttle position sensor itself, so check the sensor readings at closed throttle and look for carbon holding the plate open.
Will P0510 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 P0510 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 |
|---|---|
| P0505 | Idle Air Control System Malfunction |
| P0121 | Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance |
| P2176 | Throttle Actuator Control System – Idle Position Not Learned |
Guides that help
When it is more than a sensor
Throttle and idle codes are fixed at the throttle body, the pedal, a sensor or a leak. If those check out and the engine still runs poorly, a compression test separates a control problem from a worn engine; compare engines by code on our engines page.
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