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 thinks there's not enough fuel being mixed with the air in one side of the engine. It's like when you have too much air and not enough juice in your smoothie.
The engine control module (ECM) is detecting that the air-fuel mixture in Bank 2 is too lean, meaning there's more air than fuel.
The P1202 code indicates that the ECM has detected a lean condition in Bank 2 of the engine. The fuel trim is adjusted to maintain the right air-fuel mixture, but if it reaches its limit and still detects a lean condition, this code is triggered. This can be due to issues like vacuum leaks, faulty fuel injectors, or problems with the mass air flow sensor.
• Check Engine Light is on
• Poor engine performance
• Rough idling
• Vacuum leaks in the intake manifold
• Faulty fuel injectors
• Mass air flow sensor malfunction
ECM: Engine Control Module, the computer that controls engine functions.
Fuel Trim: Adjustments made by the ECM to the air-fuel mixture.
• Check for vacuum leaks in the intake system.
• Inspect the fuel injectors for proper operation.
• Test the mass air flow sensor.
• Repair any vacuum leaks found.
• Replace or clean faulty fuel injectors.
• Replace the mass air flow sensor if necessary.
• OBD-II scanner
• Vacuum gauge
• Multimeter
$150 - $500
Moderate
• BMW 3 Series
• Mercedes-Benz C-Class
• Audi A4
• Regularly inspect and replace air filters.
• Perform routine maintenance on fuel injectors.
• Check for and repair any vacuum leaks promptly.
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you notice performance issues.
Most vehicles have a warranty that covers emissions-related components for a certain period. Check with your manufacturer.
This code has been commonly associated with issues in vehicles with direct fuel injection systems.
Moderate – It should be addressed soon to prevent further engine damage.
Driving with a lean condition can cause increased emissions and potential engine damage.
• Engine at operating temperature
• Under normal driving conditions
The components related to this code are located in the engine bay, including the intake manifold and fuel injectors on Bank 2.
Q: Can I drive with a P1202 code?
A: It's not recommended to drive for long periods with this code as it can cause engine damage.
Q: What does 'Bank 2' mean?
A: Bank 2 refers to the side of the engine that does not contain cylinder 1, typically in V-type engines.
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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.