TorqueMech OBD Code Guide
P0312 - Cylinder 12 Misfire Detected
Cylinder 12 is misfiring often enough for the ECM to detect it.
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Check likely system
Estimate after confirmation
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Common Next Steps
Turn the code into the next check.
Inspect ignition coils
Check coil boots, carbon tracking, and whether the miss follows a swap.
Check spark plugs
Inspect gap, fouling, wear, oil, coolant, and plug-well condition.
Verify injector operation
Move to injector balance, pulse, or leak-down checks if the misfire stays.
Check compression if needed
Use compression or leak-down testing when spark and fuel checks do not move the fault.
Code Overview
Cylinder 12 is misfiring often enough for the ECM to detect it.
Common Causes
- Worn spark plug on cylinder 12
- Weak ignition coil or boot on cylinder 12
- Fuel injector problem on cylinder 12
- Low compression on cylinder 12
Diagnostic Steps
- Swap the coil or plug with another cylinder if possible
- Inspect the spark plug for wear, oil, or fuel fouling
- Check injector operation and connector fit
- Run compression or leak-down testing if the misfire stays put
Related OBD Codes
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Next Steps
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