P03C4
Cylinder 5 Pressure Variation Low
Cylinder-to-cylinder pressure variation on cylinder 5 is below the calibrated minimum — pressure stays unusually constant cycle-to-cycle, often a sign that the closed-loop combustion controller has lost authority or the sensor signal is filtered.
Cylinder-to-cylinder pressure variation on cylinder 5 is below the calibrated minimum — pressure stays unusually constant cycle-to-cycle, often a sign that the closed-loop combustion controller has lost authority or the sensor signal is filtered.
Common causes
- high
Sensor signal filtered
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-2200
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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
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Frequently asked questions
What does P03C4 mean?
P03C4 means "Cylinder 5 Pressure Variation Low". 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 P03C4?
sensor signal filtered — 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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