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 that the air and fuel mixture in cylinder 2 is too rich, which means there is too much fuel and not enough air.
The engine control module (ECM) monitors the air-fuel ratio in each cylinder. If it detects that cylinder 2 has a richer mixture than expected, it triggers this code.
P11D3 indicates that the ECM has detected an imbalance in the air-fuel ratio for cylinder 2, specifically that the mixture is too rich. This could be due to a malfunctioning fuel injector, a faulty oxygen sensor, or other issues affecting the fuel delivery or measurement.
• Check engine light is on
• Poor fuel economy
• Rough idle
• Engine misfires
• Increased emissions
• Faulty fuel injector in cylinder 2
• Malfunctioning oxygen sensor
• Leaking fuel pressure regulator
• Vacuum leaks
• Faulty mass air flow sensor
ECM: Engine Control Module
Air-Fuel Ratio: The ratio of air to fuel in the combustion mixture
Oxygen Sensor: A device that measures the oxygen level in the exhaust gases
• Check for any additional codes
• Inspect fuel injector for cylinder 2
• Test the oxygen sensor
• Check for vacuum leaks
• Inspect the mass air flow sensor
• Replace or clean the fuel injector for cylinder 2
• Replace the oxygen sensor if faulty
• Repair any vacuum leaks
• Replace the mass air flow sensor if needed
• OBD-II scanner
• Fuel pressure gauge
• Multimeter
• Vacuum leak detector
$150 - $400
Moderate
• Chevrolet Silverado
• Ford F-150
• Toyota Camry
• Regular maintenance of the fuel system
• Timely replacement of air filters
• Regular inspection of oxygen sensors
Engine Performance
• Avoid driving with this code active to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on engine components.
This code has been associated with fuel system issues and is more common in vehicles with higher mileage.
Moderate – While the vehicle may still be drivable, it should be repaired soon to avoid potential damage.
Ignoring this code can lead to increased emissions, which may be illegal in some areas.
• Engine at operating temperature
• Vehicle idling or at a steady speed
Cylinder 2 is located on the engine block, typically identified in the vehicle's service manual.
Q: Can I drive with a P11D3 code?
A: It's possible, but not recommended as it can lead to further engine damage.
Q: How can I fix a P11D3 code?
A: Diagnosis is necessary to find the exact cause. It may involve cleaning or replacing the fuel injector, oxygen sensor, or fixing vacuum leaks.
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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.