P0287 — Cylinder 9 Injector Circuit High
Drivable short-term, but fix now to avoid damage.
What P0287 means
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.
Common symptoms
- Check engine light is on
- Rough idle or engine shaking
- Engine misfire or hesitation
- Loss of power or sluggish acceleration
- Hard starting or stalling
Common causes
- Open circuit or broken wire in the injector harness
- Corroded or loose injector connector
- Failed fuel injector for cylinder 9
- Poor ground or power supply to the injector
- Faulty engine control module (less common)
Typical repair cost
$150 – $500
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0287 code?
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.
How much does it cost to fix a P0287 code?
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.
Is P0287 a serious code?
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.
What's the difference between P0287 and P0286?
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.