P0302 - Cylinder 2 Misfire Detected
P0302 is a generic powertrain diagnostic trouble code indicating Cylinder 2 Misfire Detected. It relates to the Ignition System / Misfire system.
DTC Breakdown (SAE J2012)
| System | Powertrain (P) |
| Type | Generic |
| Subsystem | Ignition System / Misfire |
| Fault Index | 02 |
| Standard | SAE J2012 / ISO 15031-6 |
What does diagnostic code P0302 mean?
The engine control module has identified that cylinder number 2 is failing to fire correctly during the combustion stroke.
Severity Level & Driveability Details
Severity: High
Unburned fuel from cylinder 2 will flood the exhaust and destroy the catalytic converter. A flashing light indicates active misfires.
Common Symptoms of P0302
- Engine stumble or hesitation under load.
- Rough running engine at idle with shaking.
- Continuous flashing check engine warning indicator on the dashboard.
- Raw fuel smell from the exhaust pipe due to Cylinder 2 misfire.
Typical Causes for P0302
- Worn or cracked spark plug in cylinder 2.
- Failed ignition coil for cylinder 2.
- Failed cylinder 2 fuel injector.
- Internal cylinder 2 compression loss (burnt valve or gasket).
Diagnostic and Troubleshooting Steps
Swap the cylinder 2 coil with cylinder 1. If the misfire shifts to cylinder 1 (P0301), replace the coil. If not, swap the spark plug, test injector pulse, and check compression.
Typical Repairs and Fixes
- Replacing the ignition coil or spark plug on cylinder 2.
- Replacing the cylinder 2 fuel injector.
- Resolving mechanical valve or head gasket leaks.
Sensor Location & Parts Involved
The ignition coil and spark plug for cylinder 2 are located on top of the cylinder head on the engine block.
Clearing Code & Recurrence
Resolve the underlying ignition or fuel fault in cylinder 2, then reset the codes using an OBD2 scanner.
Emissions & Smog Inspection Impact
Misfiring in cylinder 2 releases unburned hydrocarbons into the exhaust stream, potentially damaging the catalytic converter and raising emissions.
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Related Diagnostic Codes
Sources & References
This diagnostic guide is compiled and verified against the following authority sources:
- NHTSA Recall Database
- EPA OBD II Regulations
Frequently Asked Questions about P0302
What does the cylinder 2 misfire code P0302 mean?
The engine control module logged P0302 after detecting a combustion misfire in cylinder 2. This indicates that the fuel-air mixture is failing to ignite properly inside the cylinder 2 chamber.
Is it safe to drive with the cylinder 2 misfire code P0302 active?
No, driving with active misfires in cylinder 2 can ruin the catalytic converter.
How much does it cost to repair a cylinder 2 misfire code P0302 fault?
Replacing an ignition coil or spark plug for cylinder 2 typically costs $100-$300. Replacing the fuel injector for cylinder 2 costs $200-$450.
What are the common causes of the cylinder 2 misfire code P0302?
Trigger conditions for the cylinder 2 misfire code P0302 include: A worn or fouled spark plug in cylinder 2., Failed ignition coil or damaged spark plug wire for cylinder 2., Faulty fuel injector or poor fuel atomization in cylinder 2..
Can I clear the check engine light for cylinder 2 misfire code P0302?
Resolve the underlying ignition or fuel fault in cylinder 2, then reset the codes using an OBD2 scanner.
Will the cylinder 2 misfire code P0302 cause an inspection failure?
Misfiring in cylinder 2 releases unburned hydrocarbons into the exhaust stream, potentially damaging the catalytic converter and raising emissions.