P0312 Code - Cylinder 12 Misfire Detected
Quick Answer
When the OBD-II code P0312 appears, it indicates that Cylinder 12 Misfire has been detected in the engine. Common causes include Faulty spark plugs or ignition coils, Clogged fuel injectors or fuel filter, Vacuum leaks in the intake system. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0312 indicates Cylinder 12 Misfire Detected.
- Common causes
- Common causes include Faulty spark plugs or ignition coils, Clogged fuel injectors or fuel filter, Vacuum leaks in the intake system.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P0312 Description
When the OBD-II code P0312 appears, it indicates that Cylinder 12 Misfire has been detected in the engine. This means that the fuel in the cylinder is not igniting properly, leading to a lack of power, rough idle, and potentially harmful emissions. A misfire can cause damage to the engine over time if left unresolved, as it can lead to unburned fuel entering the exhaust system and damaging components such as the catalytic converter.
Common Causes of P0312
- Faulty spark plugs or ignition coils
- Clogged fuel injectors or fuel filter
- Vacuum leaks in the intake system
- Low compression in the cylinder
- Malfunctioning EGR valve
Symptoms of P0312
- Rough idle or shaking sensation while driving
- Loss of power or acceleration
- Increased fuel consumption
- Engine misfiring or hesitation
- Check Engine Light illuminated
How to Fix P0312
- Perform a diagnostic scan to identify the specific cylinder misfire
- Inspect ignition system components such as spark plugs and ignition coils
- Check fuel system components including fuel injectors and fuel filter
- Test for vacuum leaks in the intake system
- Conduct a compression test to check for low compression in the cylinder
Cost to Fix P0312
The typical repair costs for addressing a Cylinder 12 Misfire Detected code may range from $100 to $500, depending on the specific cause of the issue and the necessary repairs. This estimate includes parts and labor, but actual costs may vary based on the location of the repair shop, the make and model of the vehicle, and the extent of the repairs needed. It's recommended to obtain multiple quotes from different auto repair shops to ensure a competitive price.
Tech Notes for P0312
Need more information about the P0312 code?
Need more information on how to fix the P0312 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0312 code diagnosed by a professional: Find a repair shop in your area
Code P0312 Information for Specific Makes
- P0312 Mercedes-Benz — Cylinder 12 Misfire Detected
- P0312 Volkswagen — Cylinder 12 Misfire Condition
Frequently Asked Questions about P0312 Code
No Frequently Asked Questions about P0312 Code found.
Discuss the causes and fixes for P0312 OBDII Code
Code P0312 comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.