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 has detected a problem with the way cylinder number 12 is working. It's not doing its job properly in the engine.
The engine control module (ECM) monitors the power output from each cylinder. If it detects that cylinder 12 is not contributing its share of power, it triggers this code.
P0296 is logged when the ECM detects that cylinder 12 is not contributing to the engine's power balance as expected. This could be due to a misfire, fuel delivery issue, or compression problem. The ECM uses data from the crankshaft position sensor and other sensors to determine if each cylinder is providing the correct amount of power.
• Check Engine Light is on
• Rough engine idle
• Decreased engine performance
• Increased fuel consumption
• Engine misfire
• Faulty spark plug in cylinder 12
• Fuel injector issue in cylinder 12
• Low compression in cylinder 12
• Vacuum leak affecting cylinder 12
• Faulty ignition coil for cylinder 12
ECM: Engine Control Module
Misfire: A failure of the air/fuel mixture in a cylinder to ignite properly
Compression: The pressure created in a cylinder when the piston compresses the air/fuel mixture
• Check for any other codes and address them first.
• Inspect the spark plug, ignition coil, and fuel injector for cylinder 12.
• Perform a compression test on cylinder 12.
• Check for vacuum leaks around cylinder 12.
• Use a scan tool to monitor live data for cylinder performance.
• Replace faulty spark plug or ignition coil in cylinder 12.
• Clean or replace the fuel injector for cylinder 12.
• Repair any vacuum leaks found.
• Address any compression issues, such as worn piston rings or valves.
• OBD-II scanner
• Compression tester
• Multimeter
• Fuel injector cleaner
• Basic hand tools
$150 - $500
Moderate
• BMW 7 Series
• Mercedes-Benz S-Class
• Audi A8
• Regular maintenance of spark plugs and ignition coils
• Using quality fuel to prevent injector clogging
• Routine engine inspections to catch issues early
Engine Performance
• Do not ignore the Check Engine Light.
• Get a professional diagnosis if unsure.
• Regular maintenance can prevent these issues.
Check with your vehicle manufacturer for warranty coverage on engine components.
Cylinder contribution codes have been used to help diagnose misfires and engine performance issues in modern vehicles.
Moderate – While the car may still run, ignoring this issue can lead to more serious engine damage.
Driving with an engine misfire can lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle at idle or under load
Cylinder 12 is located in the engine block, typically at the rear of a V12 engine configuration.
Q: Can I drive with a P0296 code?
A: It's not recommended as it can lead to further engine damage.
Q: How can I prevent a P0296 code?
A: Regular maintenance and using quality fuel 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.