P0303
Cylinder 3 Misfire Detected
high
i Description
The ECU has detected a misfire specifically in cylinder 3.
? Common Causes
- Worn or fouled spark plug in cylinder 3
- Faulty ignition coil for cylinder 3
- Damaged spark plug wire/boot
- Faulty fuel injector for cylinder 3
- Low compression in cylinder 3
! Symptoms
- Check engine light (may flash)
- Engine vibration
- Loss of power
- Rough idle
# Diagnostic Steps
- Inspect spark plug from cylinder 3
- Swap ignition coil with another cylinder
- Test fuel injector
- Compression test on cylinder 3
⚙ Typical Fix
Replace the spark plug and/or ignition coil for cylinder 3.
Parts Needed
Spark plug, Ignition coil
Estimated Cost
$50-$400
↔ Related Codes
Q Frequently Asked Questions
Do not drive if the check engine light is flashing. A steady light allows careful, short-distance driving.
☞ Learn More
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