P0297 Vehicle Overspeed Condition

P0297 indicates a vehicle overspeed condition. Vehicle speed exceeded a calibrated limit or the controller saw an implausible high-speed event.

Code details

Generic OBD-II · P0

System: Fuel / Air
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not ignore a true overspeed event, but verify speed sensor plausibility before assuming driver operation caused it.

Symptoms of P0297

Check-engine light on, sometimes with rough or uneven running.
Hesitation, surging, or a noticeable change in fuel economy.
Occasionally hard starting or a smell of unburnt fuel.

Common causes of P0297

A failing or contaminated sensor (MAF, MAP, oxygen or air-fuel sensor).
Intake or vacuum leaks, or an exhaust leak near an upstream sensor.
Wiring, connector, or fuel-delivery problems that skew the reading.

Useful checks before replacing parts

Review freeze-frame vehicle speed, engine RPM, gear, wheel-speed data, throttle position, and transmission state when the code set.
Inspect vehicle speed sensor data, ABS wheel-speed plausibility, tire size programming, transmission output speed, and scan-tool units.
Check whether the event followed actual overspeed, incorrect tire programming, sensor dropout, or a transmission speed signal fault.

Related OBD-II codes

These nearby fuel / air entries can help compare wording and pin down the fault area.