Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the injector for cylinder 2 in your car's engine. It's like a wire is touching something it shouldn't, causing a short circuit.
The code indicates an electrical issue where the low side of the high-pressure injector for cylinder 2 is shorted to the coil circuit.
The P31F5 code is set when the engine control module (ECM) detects that the low side of the high-pressure fuel injector for cylinder 2 has an electrical short to the coil circuit. This can cause improper fuel delivery and engine performance issues.
• Engine misfire
• Poor fuel economy
• Check engine light on
• Damaged wiring or connectors
• Faulty fuel injector
• Short circuit in the injector circuit
Injector: A device that sprays fuel into the engine's cylinders.
Short Circuit: An electrical circuit that allows current to travel along an unintended path.
• Inspect wiring and connectors for damage.
• Check the resistance of the injector coil.
• Perform a continuity test on the injector circuit.
• Repair or replace damaged wiring.
• Replace the faulty injector.
• Clear the code and test drive the vehicle.
• Multimeter
• OBD-II scanner
• Basic hand tools
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect and maintain wiring harnesses.
• Use quality fuel to prevent injector clogging.
• Perform regular engine tune-ups.
Engine Performance
• Avoid driving the vehicle until the issue is fixed to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check if your vehicle's powertrain warranty covers injector-related repairs.
This code has been associated with vehicles experiencing injector-related electrical issues, often due to wear and tear or manufacturing defects.
Moderate – Addressing this issue promptly can prevent further engine damage.
Driving with a misfiring engine can lead to increased emissions and potential safety hazards.
• Engine running
• Warm engine temperature
The fuel injector for cylinder 2 is located on the engine's intake manifold, near the cylinder head.
Q: Can I drive with a P31F5 code?
A: It's not recommended to drive with this code, as it can lead to engine damage and poor performance.
Q: How can I prevent injector issues?
A: Regular maintenance and using quality fuel can help prevent injector problems.
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Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.