P03C6
Cylinder 5 Combustion Performance
The closed-loop combustion controller reports that combustion performance on cylinder 5 is below the calibrated quality metric. Computed from the cylinder pressure trace — IMEP (indicated mean effective pressure), CA50 (50% mass burnt angle) or peak pressure deviates from the model.
The closed-loop combustion controller reports that combustion performance on cylinder 5 is below the calibrated quality metric. Computed from the cylinder pressure trace — IMEP (indicated mean effective pressure), CA50 (50% mass burnt angle) or peak pressure deviates from the model.
Common causes
- high
Injector flow rate drift
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-2750
- low
Gateway module routing CAN messages incorrectly
Less common, but worth ruling out after the more likely causes.
Typical part cost: $220-2750
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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 P03C6 mean?
P03C6 means "Cylinder 5 Combustion Performance". 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 P03C6?
injector flow rate drift; gateway module routing can messages incorrectly; can terminating resistor (120 ω) drifted out of spec — 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 points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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