Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that the engine's computer has detected that the air and fuel mixture in cylinder 3 is not right. It's getting too much air and not enough fuel, which can make the engine run poorly.
The engine control module (ECM) monitors the air-fuel ratio for each cylinder. If it detects that the mixture is too lean in cylinder 3, it triggers the P11D4 code.
A lean condition in cylinder 3 indicates that there is too much air and not enough fuel in the combustion process. This can be caused by issues such as a vacuum leak, a malfunctioning fuel injector, or a problem with the mass air flow sensor. The ECM uses data from various sensors to maintain the optimal air-fuel mixture, and an imbalance can lead to performance issues and increased emissions.
• Rough idling
• Poor fuel economy
• Engine misfire
• Check Engine Light on
• Reduced engine performance
• Vacuum leak affecting cylinder 3
• Faulty fuel injector on cylinder 3
• Mass air flow sensor malfunction
• Exhaust leak near cylinder 3
• Faulty oxygen sensor
ECM: Engine Control Module
Lean Condition: A situation where there is too much air and not enough fuel in the air-fuel mixture.
• Use an OBD-II scanner to confirm the code.
• Inspect the intake system for leaks.
• Check the fuel injector for cylinder 3.
• Test the mass air flow sensor.
• Inspect the oxygen sensors.
• Repair any vacuum leaks.
• Replace or clean the fuel injector for cylinder 3.
• Replace the mass air flow sensor if faulty.
• Repair any exhaust leaks.
• Replace faulty oxygen sensors.
• OBD-II scanner
• Vacuum gauge
• Fuel injector cleaner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Chevrolet Silverado
• Ford F-150
• Toyota Camry
• Regularly inspect and maintain the fuel system.
• Check for vacuum leaks periodically.
• Ensure sensors are clean and functioning.
Engine Performance
• Have the vehicle checked by a professional if you notice performance issues.
• Do not ignore the Check Engine Light.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with vehicles that have high mileage or have not been maintained regularly.
Moderate – This issue should be addressed promptly to avoid further engine damage.
Driving with a lean condition can increase emissions and may not pass emissions testing.
• Engine at operating temperature
• Vehicle idling
Cylinder 3 is typically located on the engine block, and its position can vary depending on the engine configuration.
Q: Can I drive with a P11D4 code?
A: While you may be able to drive short distances, it's not recommended to ignore this code as it can lead to engine damage.
Q: What happens if I don't fix a lean condition?
A: Ignoring a lean condition can cause engine misfires, reduced performance, and potential damage to engine components.
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Fitment Required · Vehicle-fitment part
Relevant when the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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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.