Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer has noticed that cylinder number 11 isn't working properly. It's like one of the car's 'legs' isn't moving right, causing the car to stumble a bit when it runs.
The engine control module (ECM) has detected a misfire in cylinder 11. This means that the combustion process in this cylinder is not occurring as expected.
A misfire in cylinder 11 means that the air/fuel mixture in that cylinder is not igniting properly. This can be due to issues with fuel delivery, spark, or compression in that specific cylinder.
• Rough engine idle
• Check Engine Light illuminated
• Poor fuel economy
• Engine hesitation or stumbling
• Increased emissions
• Faulty spark plug in cylinder 11
• Defective ignition coil for cylinder 11
• Fuel injector issue in cylinder 11
• Vacuum leak affecting cylinder 11
• Low compression in cylinder 11
ECM: Engine Control Module, the computer that controls the engine's operation.
Misfire: Failure of the air/fuel mixture in a cylinder to ignite properly.
• Use an OBD-II scanner to confirm the P0311 code.
• Inspect the spark plug and ignition coil for cylinder 11.
• Check the fuel injector for cylinder 11.
• Perform a compression test on cylinder 11.
• Inspect for vacuum leaks around cylinder 11.
• Replace the spark plug in cylinder 11.
• Replace or repair the ignition coil for cylinder 11.
• Clean or replace the fuel injector for cylinder 11.
• Repair any vacuum leaks found near cylinder 11.
• Address any compression issues in cylinder 11.
• OBD-II scanner
• Spark plug socket
• Compression tester
• Multimeter
• Fuel injector cleaning kit
$150 - $500
Moderate
• High-performance vehicles with more than 10 cylinders
• Luxury SUVs with V12 engines
• Certain sports cars with V12 engines
• Regularly replace spark plugs and ignition components.
• Use high-quality fuel.
• Perform regular engine maintenance checks.
Engine Performance
• Avoid driving the vehicle until the issue is fixed to prevent further damage.
• Regularly maintain the vehicle to avoid misfires.
• Consult with a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer for powertrain warranty coverage.
Misfire codes have been common since the introduction of OBD-II systems, often indicating issues with ignition or fuel delivery.
High – Driving with a misfire can cause damage to the catalytic converter and other engine components.
Ignoring engine misfires can lead to increased emissions and potential safety hazards.
• Engine running
• Vehicle at operating temperature
Cylinder 11 is located in the engine block, typically on the side with the odd-numbered cylinders in a V-type engine.
Q: Can I drive with a P0311 code?
A: It's not recommended to drive with a misfire as it can cause further engine damage.
Q: How do I know if cylinder 11 is misfiring?
A: You may notice rough idling, poor acceleration, and the Check Engine Light may be on.
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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.