P0289 — Cylinder 10 Injector Circuit High

What does P0289 mean on this engine?

P0289 identifies a high voltage condition in the cylinder 10 injector circuit. It commonly results from an open circuit, high resistance, a poor connector, or a failed injector rather than an actual over-fueling condition.

Can the vehicle be driven with P0289 stored?

Only cautiously if the engine is otherwise smooth. Continued driving with an active cylinder 10 misfire may overheat the exhaust system and damage the catalytic converter, so prompt diagnosis is recommended.

Does P0289 prove that the cylinder 10 injector is bad?

No. P0289 can be caused by an open wire, corroded terminal, damaged splice, or engine-control-module driver. The circuit and injector should be tested before replacing the injector.

How is the correct cylinder 10 injector located?

Use the manufacturer wiring diagram and cylinder-numbering chart. P0289 refers to the electrical circuit designated as cylinder 10, which may not match the cylinder's obvious physical position from the front of the engine.

When your scan tool pulls code P0289, it's telling you the engine control module has detected a problem with the fuel injector circuit for cylinder 10 — specifically, the voltage on that circuit is running higher than it should. This falls under the powertrain category in the OBD2 standard, which means the engine management system is watching the fuel delivery and mixture control circuit in real time and has decided something is out of spec.

Cylinder numbering varies by engine layout. On a traditional inline engine, cylinders are counted from the front — usually the end with the timing belt or chain. On V-type engines, the numbering order depends entirely on the manufacturer, so you'll need to pull up the firing order diagram for your specific model before diving into diagnostics. Why does this matter for your wallet? Because on some engines, cylinder 10 sits deep under the intake manifold, which can add significant labor time to any repair that involves the injector itself.

The phrase "circuit high" tells you exactly what the PCM saw: voltage on the cylinder 10 injector signal line that is sitting close to battery voltage when it should be pulsing. That excess voltage points to one of a few things — a wire shorted to a power source, an open ground return that leaves the circuit floating high, or a failed injector that is pulling the signal line up. To trigger P0289, the control module usually needs to see this condition persist across multiple drive cycles. It also captures a freeze frame — a snapshot of RPM, engine load, coolant temperature, and vehicle speed at the exact moment the fault occurred. Reading that snapshot first before doing anything else will often point you straight at the root cause and cut your diagnostic time in half.

Symptoms of P0289

If your vehicle is setting P0289, you'll likely notice one or more of the following:

• The engine idles roughly, shakes, or stumbles, especially when stationary.
• The Check Engine light stays on or may flash intermittently under load.
• Acceleration feels flat or sluggish, with noticeably reduced power when you ask the engine to work harder.
• The engine cranks longer than normal before starting, or may require several attempts.
• In more severe cases, a raw fuel smell becomes noticeable around the tailpipe or engine bay.
• You may see a measurable drop in miles per gallon compared to your normal driving pattern.

Common causes of P0289

P0289 is most often rooted in one of the following issues, listed from most to least likely based on field experience:

• A short between the injector signal wire and a constant power source, keeping the circuit artificially high.
• A failed cylinder 10 fuel injector that is internally shorted and pulling the signal line up.
• An open or broken ground circuit for the cylinder 10 injector, preventing proper return path for the signal.
• A faulty fuel pressure regulator or a failing fuel rail pressure sensor feeding bad data back to the PCM.
• A weak fuel pump or a severely restricted fuel filter that cannot maintain proper rail pressure.
• Clogged or leaking fuel injectors that throw off the mixture enough to confuse the control module.
• Vacuum leaks or intake tract damage that skews the air-fuel ratio and masks the real electrical problem.
• Contaminated or incorrect fuel sitting in the tank, affecting pressure and spray pattern across all cylinders.

How to diagnose P0289

A systematic approach keeps you from throwing parts at the problem. Follow these steps in order:

1. Connect your OBD2 scanner and confirm P0289 is stored in permanent memory. Save the freeze frame data before clearing anything — that record of engine conditions at the time of failure is your roadmap.
2. Pull all stored and pending codes. If other fuel or sensor codes are present, they often point to the real culprit behind P0289. Check for any applicable technical service bulletins (TSBs) for your make and model — manufacturers sometimes publish known fixes or PCM updates for recurring injector circuit issues.
3. Inspect the wiring harness and connectors at the cylinder 10 injector and the fuel rail. Look for damaged insulation, broken terminals, corrosion, or loose plugs that could cause a short or an open circuit.
4. Disconnect the cylinder 10 injector connector and measure signal voltage at the harness side. If the reading is still high with the injector unplugged, the wiring harness has a short to power. If the voltage drops to normal, the injector itself is the problem.
5. Test fuel pressure at the rail with a gauge while the engine is running at idle and under varying load. Compare your readings against the factory specification for your vehicle.
6. Review live data for short-term and long-term fuel trim values. Positive or negative trends across both banks tell you which direction the mixture is being pulled and whether the issue is rich or lean.
7. Clear the code, complete a full drive cycle that recreates the conditions stored in the freeze frame, and verify P0289 does not return.

Repair options and costs

Tackle the simple and inexpensive possibilities before committing to major repairs. Here are the typical part and labor costs for the most common P0289 fixes, based on independent shop rates:

• Replace the fuel pressure regulator or fuel rail pressure sensor — $150–$450. This is often the culprit in high-circuit injector faults because a bad regulator can send erratic pressure data back through the wiring.
• Replace the fuel pump — $400–$900. A failing pump that cannot maintain rail pressure will trigger a cascade of fuel delivery codes, including circuit-high injector faults.
• Replace the fuel filter — $80–$200. While rarely the sole cause of a circuit fault, a clogged filter can amplify pressure irregularities that contribute to the problem.
• Clean or replace the injectors — $200–$800. If the cylinder 10 injector itself has an internal short, cleaning will not fix it and replacement is the only real solution.

All told, fixing P0289 typically runs between $80 and $900 depending on what actually failed. The most expensive repair — a fuel pump — is almost never where you should start. A proper diagnosis before you buy parts will almost always save you money and prevent unnecessary work.

Driving safety verdict

Drive with caution. A cylinder 10 injector circuit fault can lead to a leaning-out or rich-running condition that causes hesitation, stalling, or misfires — particularly risky in heavy traffic. If the problem is severe, unburned fuel reaching the catalytic converter can cause overheating and irreversible damage to that expensive component. Do not ignore the code or plan a long highway trip until the underlying cause is identified and resolved. Get it diagnosed promptly, then repair based on what the testing actually shows.