Drivable short-term, but fix now to avoid damage.
This code means your engine's computer detected a misfire in cylinder 12, so that cylinder isn't completing its combustion correctly. It's usually caused by worn spark plugs, a bad ignition coil, fuel injector trouble, or low compression in that cylinder. Repairs typically start with new spark plugs and coils, and it's a common issue that's often fixable without major engine work.
$150 – $1200
Varies by vehicle and root cause.
Only for a short distance if you must. A misfire can damage your catalytic converter and worsen quickly, especially with a flashing light. Get it diagnosed as soon as possible.
Most repairs fall between $150 and $1,200. Spark plug and coil replacements are cheaper, while injector or compression repairs cost more.
Yes. A misfire reduces performance, wastes fuel, and can damage expensive emissions parts if left unaddressed. A flashing light makes it urgent.
On some vehicles P0320 relates to the ignition or engine speed input circuit rather than a cylinder 12 misfire, so the exact meaning can vary by manufacturer. A proper scan tool reading the manufacturer-specific definition is the safest way to confirm what your car means.