Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's computer thinks there's not enough air going into the engine on one side, which might make it run poorly.
The engine control module (ECM) is detecting a lower than expected air flow from the oxygen sensor readings on bank 2.
The P111D code indicates that the oxygen sensor on bank 2 is reporting a mass or volume air flow that is too low. This can affect the air-fuel mixture and engine performance.
• Check Engine Light on
• Poor fuel economy
• Rough idle
• Faulty oxygen sensor
• Vacuum leak
• Dirty or faulty mass air flow sensor
ECM: Engine Control Module
Oxygen Sensor: A device that measures the oxygen level in the exhaust gases
• Use an OBD-II scanner to verify the code.
• Inspect the oxygen sensor on bank 2 for damage or wear.
• Check for vacuum leaks around the intake manifold.
• Replace the oxygen sensor if faulty.
• Repair any vacuum leaks.
• Clean or replace the mass air flow sensor.
• OBD-II scanner
• Wrench set
• Vacuum gauge
$100 - $400
Moderate
• BMW 3 Series
• Ford F-150
• Chevrolet Silverado
• Regularly clean the mass air flow sensor.
• Inspect and replace air filters as needed.
• Check for vacuum leaks periodically.
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has been associated with vehicles experiencing poor air-fuel mixture control, often due to sensor degradation over time.
Moderate – Address the issue soon to avoid potential engine performance problems.
Operating a vehicle with unresolved diagnostic trouble codes may lead to increased emissions and could be illegal in some regions.
• Engine at normal operating temperature
• Vehicle in closed-loop operation
The oxygen sensor for bank 2 is located on the exhaust manifold of the engine's second bank.
Q: Can I drive with a P111D code?
A: It's not recommended to drive for long periods with this code, as it can lead to poor engine performance.
Q: How do I know if the oxygen sensor is faulty?
A: A faulty oxygen sensor may cause rough idling, poor fuel economy, and trigger the Check Engine Light.
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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.
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Fitment Required · Vehicle-fitment part
Relevant for airflow, fuel-trim, and intake-metering faults after confirming the sensor is actually at fault.
Airflow and fuel-trim codes can involve the mass air flow sensor after proper diagnosis.
Verify the sensor design and fitment for your exact vehicle.
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.