OBD-II DTC · POWERTRAIN · Severity: HIGH
P0303: Cylinder 3 Misfire Detected
Combustion misfire isolated to Cylinder 3.
| DTC Code | P0303 |
|---|---|
| Standard Definition | Cylinder 3 Misfire Detected |
| Subsystem | POWERTRAIN |
| Urgency / Severity | HIGH |
| Standard Reference | SAE J2012 / ISO 15031-6 |
1. Symptoms
- Rough idle
- Hesitation under load
- MIL illuminated
2. Common Root Causes
- Faulty Cylinder 3 coil pack or spark plug
- Injector wiring or spray pattern fault
- Mechanical compression loss
3. Diagnostic Procedure
- Swap coil pack with another cylinder
- Inspect spark plug and high-tension boot
- Test injector pulse and cylinder compression