P02A9
Cylinder 4 - Injector Leaking
Cylinder 4 injector leaking fuel between commanded openings. A flow-deviating injector throws off cylinder balance — adjacent cylinders run leaner/richer to compensate, often masking the root cause until the trim limit is hit.
Cylinder 4 injector leaking fuel between commanded openings. A flow-deviating injector throws off cylinder balance — adjacent cylinders run leaner/richer to compensate, often masking the root cause until the trim limit is hit.
Common causes
- high
Injector seat or seal leaking
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1650
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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 P02A9 mean?
P02A9 means "Cylinder 4 - Injector Leaking". It is a generic OBD-II code that points to a fault in the fuel & air metering (injector circuit).
What are the most common causes of P02A9?
injector seat or seal leaking — 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?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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