P2289: Injector Control Pressure Too High - Engine Off

What it means

With the engine off, injector control pressure is higher than the expected limit. The code does not by itself establish why pressure remains high.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

The injector control pressure system maintains pressure for the injection system, and the sensor reports that pressure to the control module. P2289 sets when the module detects pressure above its expected limit with the engine off, when pressure should have fallen; the code alone does not show whether pressure is trapped or misreported.

Common causes

Most likely first.

1. Pressure regulator or control valve stuck
2. Pressure sensor or wiring reporting an incorrect value
3. Pressure trapped by a faulty check valve
4. High-pressure oil system fault, where fitted

Symptoms

• Check-engine light may illuminate
• Hard starting or extended cranking
• Rough running or stalling
• Reduced power

How to diagnose it

1. Save the freeze-frame data and compare injector control pressure just after shutdown and before the next start to see whether the reading remains high.
2. With the engine off, inspect the pressure sensor connector and wiring for damage or poor contact that could hold the signal high.
3. Compare the sensor reading with any available pressure data or a suitable independent test to check whether pressure is actually retained.
4. Check the regulator or control-valve circuit and operation for a valve that remains in the wrong position after shutdown.
5. If pressure remains high despite correct sensor operation, test the check valve and, where fitted, the high-pressure oil system against the manufacturer's specification.

Common fixes

• Repair a damaged sensor connector or wiring that biases the reading.
• Replace a pressure sensor that fails testing against the manufacturer's specification.
• Repair or replace a regulator, control valve, or check valve that traps pressure after shutdown.
• Repair a verified high-pressure oil system fault, where fitted.

Can I keep driving?

Avoid repeated long cranking if starting is difficult, and do not rely on the vehicle if it stalls or loses power. Arrange diagnosis soon, since retained pressure or a false reading may affect starting and running.