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 is a problem with the fuel injector for cylinder 6 in your car. The computer is saying it's getting too much power.
The engine control module (ECM) has detected a high voltage condition in the high side circuit of the fuel injector for cylinder 6.
The P31CB code indicates that the ECM has detected a high voltage condition in the high side circuit of the high-pressure fuel injector for cylinder 6. This could be due to a short circuit, faulty wiring, or a malfunctioning injector.
• Check Engine Light on
• Poor engine performance
• Increased fuel consumption
• Faulty fuel injector
• Short circuit in the wiring
• Faulty ECM
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 faulty injector.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance checks
• Timely fuel injector cleaning
• Inspect wiring for wear and tear
Engine Performance
• Do not ignore the Check Engine Light.
• Seek professional diagnosis if unsure.
• Regularly maintain your vehicle.
Check with your vehicle manufacturer for specific warranty coverage on fuel injectors.
This code has been associated with high-pressure fuel systems in modern vehicles, particularly those with direct injection.
Moderate – Addressing this issue promptly can prevent further engine damage.
Operating a vehicle with a malfunctioning injector could lead to increased emissions and potential safety risks.
• Engine running
• Vehicle stationary
The fuel injector for cylinder 6 is located on the engine, typically near the intake manifold.
Q: Can I drive with a P31CB code?
A: It's not recommended to drive for long with this code as it can lead to further engine damage.
Q: How serious is a P31CB code?
A: While not immediately critical, it should be addressed soon to prevent performance issues.
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