Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer noticed that the spark in cylinder number 12 didn't last as long as it should. It's like when a sparkler goes out too quickly.
The Engine Control Module (ECM) monitors the spark duration in each cylinder. If the spark in cylinder 12 is too short, it triggers this code.
P1312 indicates that the ECM has detected an issue with the ignition system in cylinder 12, specifically that the spark duration is shorter than expected. This can affect the combustion process and engine performance.
• Engine misfire
• Poor fuel economy
• Check Engine Light illuminated
• Faulty ignition coil
• Worn spark plug
• Wiring issues in the ignition system
ECM: Engine Control Module
Ignition Coil: A component that transforms the battery's voltage to create a spark.
• Use an OBD-II scanner to confirm the code.
• Inspect the ignition coil for cylinder 12.
• Check the spark plug for wear or damage.
• Replace the faulty ignition coil.
• Replace the spark plug for cylinder 12.
• Repair or replace damaged wiring.
• OBD-II scanner
• Multimeter
• Spark plug socket
$100 - $300
Moderate
• BMW 7 Series
• Mercedes-Benz S-Class
• Audi A8
• Regularly inspect and replace spark plugs.
• Maintain ignition system components.
• Perform regular vehicle maintenance.
Engine Performance
• Have the vehicle inspected by a professional.
• Avoid driving the vehicle hard until repaired.
Check with the vehicle manufacturer for specific warranty coverage on ignition components.
This code is commonly associated with high-performance engines that have more cylinders.
Moderate – It can affect engine performance and should be addressed soon.
Driving with a misfire can lead to further engine damage and increased emissions.
• Engine at operating temperature
• Vehicle stationary
The ignition coil and spark plug for cylinder 12 are located on the engine block, typically on the passenger side for V12 engines.
Q: Can I drive with a P1312 code?
A: It's not recommended as it can cause further engine damage.
Q: How can I prevent this code from appearing?
A: Regular maintenance of the ignition system can help prevent this issue.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.