Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble reading a signal from cylinder 3, which helps it know if the engine is working properly.
The engine control module (ECM) detects a low voltage signal from the ion current sensing circuit in cylinder 3, indicating a potential issue with combustion monitoring.
The P289A code is triggered when the ECM identifies that the ion current sense circuit for cylinder 3 is reporting a voltage lower than expected. This circuit is responsible for monitoring the ionization current during combustion, which helps in detecting misfires and optimizing ignition timing.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty ion current sensor
• Wiring issues such as shorts or open circuits
• ECM malfunction
ECM: Engine Control Module, the computer that controls engine functions.
Ion Current Sensor: A device that measures the ionization current in the combustion chamber to monitor combustion quality.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to the ion current sensor for damage.
• Test the ion current sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the ion current sensor if faulty.
• Update or reprogram the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wiring diagram
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance checks
• Ensure proper wiring connections
• Use quality fuel to avoid sensor contamination
Sensor Issue
• Do not ignore the Check Engine Light.
• Get a professional diagnosis to prevent further damage.
Check with the vehicle manufacturer for warranty coverage on sensor-related issues.
The P289A code is relatively uncommon and typically associated with specific vehicle models that use advanced ion sensing technology.
Moderate – Addressing the issue promptly can prevent further engine performance problems.
Driving with an unresolved engine issue may lead to increased emissions and potential safety hazards.
• Engine at operating temperature
• Vehicle stationary
The ion current sensor is typically located near the ignition coil or spark plug of cylinder 3.
Q: What happens if I ignore the P289A code?
A: Ignoring the code can lead to poor engine performance and higher fuel consumption.
Q: Can I drive my car with the P289A code?
A: It's possible, but not recommended as it can cause further damage to the engine.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.