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 3 is too rich, meaning there's too much fuel and not enough air.
The engine control module (ECM) monitors the air-fuel ratio in each cylinder. When it detects that the mixture in cylinder 3 is too rich, it triggers this code.
The P11D5 code indicates that the ECM has determined that the air-fuel ratio in cylinder 3 is not within the expected range, with too much fuel present. This can cause inefficient combustion and increased emissions.
• Check engine light on
• Poor fuel economy
• Rough engine idle
• Faulty fuel injector in cylinder 3
• Leaking intake manifold gasket
• Faulty oxygen sensor
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the fuel injector for cylinder 3.
• Check for vacuum leaks around the intake manifold.
• Replace the faulty fuel injector.
• Repair or replace the intake manifold gasket.
• Replace the oxygen sensor if faulty.
• OBD-II scanner
• Fuel injector tester
• Vacuum gauge
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance of fuel injectors
• Routine checks for vacuum leaks
• Timely replacement of oxygen sensors
Engine Performance
• Avoid driving aggressively until the issue is resolved.
• Monitor fuel consumption for any unusual patterns.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with fuel system issues in various models, often linked to injector or sensor faults.
Moderate – Addressing this issue promptly can prevent further engine damage and improve fuel efficiency.
Ignoring this code can lead to increased emissions, which may not comply with local environmental regulations.
• Engine at operating temperature
• Vehicle at idle
The fuel injector for cylinder 3 is located on the engine block, typically accessible from the top of the engine.
Q: Can I drive with a P11D5 code?
A: It's not recommended as it can lead to poor performance and increased emissions.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to more serious engine problems and higher repair costs.
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.
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.