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 the computer in your car is having trouble controlling a part that helps open and close a valve in the engine. It's like a switch that's not working right for one of the engine's parts.
The P3455 code indicates a problem with the electrical circuit that controls the exhaust valve for cylinder 7. The circuit is reading a lower voltage than expected.
The P3455 code is triggered when the Engine Control Module (ECM) detects that the voltage in the exhaust valve control circuit for cylinder 7 is below the specified range. This could be due to wiring issues, a faulty valve actuator, or a problem with the ECM itself.
• Check Engine Light illuminated
• Reduced engine performance
• Engine misfire or rough idling
• Faulty exhaust valve actuator
• Damaged or corroded wiring or connectors
• Faulty Engine Control Module (ECM)
ECM: Engine Control Module, the computer that controls engine functions.
Actuator: A device that controls a mechanism or system.
• Use an OBD-II scanner to confirm the code and check for other related codes.
• Inspect the wiring and connectors for cylinder 7's exhaust valve actuator.
• Test the exhaust valve actuator for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the exhaust valve actuator if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect and maintain engine wiring.
• Ensure timely servicing of the vehicle.
• Avoid harsh driving conditions that may stress engine components.
Engine Performance
• If the Check Engine Light is on, avoid driving the vehicle until it is diagnosed.
• Have a professional mechanic inspect the vehicle if you notice performance issues.
Check with your vehicle manufacturer as emissions-related components may be covered under warranty.
This code has been observed in vehicles with higher mileage or those that have not been regularly maintained.
Moderate – While the vehicle may still be drivable, it is recommended to address the issue promptly to avoid further damage.
Driving with an unresolved engine code may lead to increased emissions and potential safety risks.
• Engine at operating temperature
• Vehicle in a controlled environment
The exhaust valve actuator for cylinder 7 is located on the engine block, typically near the cylinder head.
Q: Can I drive my car with a P3455 code?
A: It's not recommended to drive with this code active as it can lead to further engine damage.
Q: How can I reset the P3455 code?
A: After repairs, the code can be cleared using an OBD-II scanner, but make sure the issue is fixed first.
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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.