Drivable short-term, but fix now to avoid damage.
This code means the engine computer detected high voltage or an open condition in the circuit that controls the fuel injector for cylinder 9. It usually points to an open circuit, a broken wire, a poor connector, or a failed injector. It's a fairly common electrical fault and is often fixable by repairing the wiring or replacing a single injector without major engine work.
$150 – $500
Varies by vehicle and root cause.
For short distances, usually yes, but it's not a good idea long term. A non-firing cylinder can damage the catalytic converter and leave you with a much bigger bill, so have it looked at soon.
Expect roughly $150 to $500. A wiring or connector repair sits at the lower end, while replacing the cylinder 9 injector plus diagnosis costs more.
Yes, it's fairly serious because it can stop a cylinder from firing. The car may still run, but you risk converter damage and rough performance if you ignore it.
P0287 means the circuit voltage is too high or open, while P0286 means it's too low or shorted. Both affect cylinder 9's injector, but the wiring and components a technician checks differ.