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 electrical connection to the injector for cylinder 6 in your car's engine. It's like when a wire gets crossed and causes a problem.
The code indicates that the high side of the injector circuit for cylinder 6 is shorted to the coil, which can disrupt proper fuel injection.
The P31B6 code is triggered when the Engine Control Module (ECM) detects a short circuit between the high side of the injector for cylinder 6 and the ignition coil. This can cause issues with fuel delivery and engine performance.
• Engine misfire
• Poor fuel economy
• Check Engine Light illuminated
• Faulty injector for cylinder 6
• Damaged wiring or connectors
• Short circuit in the injector circuit
ECM: Engine Control Module
Injector: A device that sprays fuel into the engine's cylinders
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for cylinder 6 injector.
• Test the injector for proper operation.
• Repair or replace damaged wiring.
• Replace the injector for cylinder 6 if faulty.
• Clear the code and test drive the vehicle.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Dodge Ram
• Regularly inspect wiring and connectors.
• Ensure proper maintenance of the fuel system.
• Avoid harsh driving conditions that can damage components.
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regular maintenance can help prevent such issues.
Check with your vehicle manufacturer for specific warranty coverage related to the fuel injection system.
This code has been associated with issues in vehicles with direct fuel injection systems, especially in models with high mileage.
Moderate – It's important to address this issue to prevent further engine damage.
Driving with a misfiring engine can lead to increased emissions and potential safety hazards.
• Engine at operating temperature
• Vehicle stationary
The injector for cylinder 6 is located on the engine block, near the intake manifold.
Q: Can I drive with a P31B6 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to engine damage.
Q: How can I prevent injector issues?
A: Regular maintenance and using high-quality fuel can help prevent injector problems.
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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.