P03A5
Cylinder 2 Pressure Too High
Cylinder 2 measured peak combustion pressure is above the calibrated maximum — typically pre-ignition, knock, over-fuelling, or runaway combustion.
Cylinder 2 measured peak combustion pressure is above the calibrated maximum — typically pre-ignition, knock, over-fuelling, or runaway combustion.
Common causes
- high
Pre-ignition or knock
One of the most commonly reported causes for this code — check this first.
Typical part cost: $440-4400
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P03A5 mean?
P03A5 means "Cylinder 2 Pressure Too High". It is a generic OBD-II code that points to a fault in the ignition system or misfire.
What are the most common causes of P03A5?
pre-ignition or knock — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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