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 there is a problem with the injector for cylinder 6 in your car. It's not getting enough power to work properly.
The engine control module (ECM) has detected that the electrical circuit for the high-pressure injector in cylinder 6 is showing a low voltage condition.
The P31CA code is triggered when the ECM detects a low voltage condition in the high side circuit of the high-pressure injector for cylinder 6. This can affect the fuel delivery to the cylinder, potentially causing engine performance issues.
• Engine misfire
• Reduced engine performance
• Check Engine Light illuminated
• Faulty injector
• Wiring issues or poor connections
• Faulty ECM
ECM: Engine Control Module
Injector: A device that sprays fuel into the engine's cylinders
• Inspect the wiring and connectors for cylinder 6 injector.
• Test the injector for proper resistance.
• Check the ECM for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty injector.
• Reprogram or replace the ECM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $800
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance and inspection of the fuel system.
• Use high-quality fuel to prevent injector clogging.
• Ensure proper electrical connections.
Engine Performance
• Do not ignore the Check Engine Light.
• Get the vehicle diagnosed by a professional.
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
Check with the vehicle manufacturer for warranty coverage on fuel system components.
This code has been associated with injector and wiring issues in vehicles with direct fuel injection systems.
High – This issue can lead to severe engine performance problems if not addressed promptly.
Driving with a malfunctioning injector can lead to increased emissions and potential engine damage.
• Engine running
• Proper fuel pressure
The injector for cylinder 6 is located on the engine, typically under the intake manifold.
Q: Can I drive my car with a P31CA code?
A: It's not recommended to drive with this code active, as it can cause engine damage and poor performance.
Q: How urgent is it to fix a P31CA code?
A: It is urgent to fix this code to prevent further engine damage and ensure proper vehicle performance.
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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.