Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means there's a problem with the part of the car that sprays fuel into the engine. It's like when a water gun gets stuck and sprays too much water.
The code indicates that the electrical circuit controlling the fuel injector for cylinder 2 is experiencing higher than normal voltage.
P31C3 is triggered when the Engine Control Module (ECM) detects a high voltage condition in the high side circuit of the high-pressure fuel injector for cylinder 2. This could be due to a short circuit or an issue with the injector itself.
• Engine misfire
• Poor fuel economy
• Check engine light on
• Faulty fuel injector
• Short circuit in the wiring
• Faulty ECM
ECM: Engine Control Module
Injector: A device that delivers fuel into the engine
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the fuel injector's resistance
• Replace the faulty fuel injector
• Repair or replace damaged wiring
• Replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Screwdriver set
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance checks
• Use quality fuel
• Inspect wiring regularly
Engine Performance
• Do not ignore the check engine light
• Get the vehicle inspected by a professional
• Avoid driving long distances until fixed
Check with the vehicle manufacturer for warranty coverage on engine components.
This code has been associated with injector issues in vehicles with direct fuel injection systems.
High – This issue can lead to engine performance problems and should be addressed promptly.
Driving with a malfunctioning injector can cause further engine damage and may not comply with emissions regulations.
• Engine at operating temperature
• Vehicle in park or neutral
The fuel injector for cylinder 2 is located on the engine block, usually under the intake manifold.
Q: Can I drive with a P31C3 code?
A: It's not recommended as it can cause further engine damage.
Q: How do I reset the check engine light?
A: After fixing the issue, you can use an OBD-II scanner to clear the code.
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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.