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 air going into the engine on one side, which can make it run poorly.
The P0492 code indicates that the secondary air injection system is not providing enough air flow to the exhaust on bank 2 of the engine.
The secondary air injection system helps reduce emissions by injecting fresh air into the exhaust stream to help burn off excess fuel. Bank 2 refers to the side of the engine opposite bank 1. When the PCM (Powertrain Control Module) detects insufficient air flow in this system, it triggers the P0492 code.
• Check Engine Light is on
• Increased emissions
• Possible engine performance issues
• Faulty air pump
• Blocked or leaking air injection hoses
• Faulty air injection check valve
PCM: Powertrain Control Module, the car's main computer that controls engine functions.
Bank 2: The side of the engine opposite bank 1, often the side without cylinder 1.
• Use an OBD-II scanner to confirm the code.
• Inspect air injection hoses for leaks or blockages.
• Test the air pump for proper operation.
• Replace faulty air pump.
• Repair or replace damaged hoses.
• Replace faulty check valve.
• OBD-II scanner
• Multimeter
• Vacuum pump
$150 - $600
Moderate
• BMW 3 Series
• Mercedes-Benz C-Class
• Audi A4
• Regularly inspect air injection components.
• Ensure proper maintenance of the vehicle.
• Use quality fuel to reduce emissions.
Emission Control Issue
• Address the issue promptly to avoid increased emissions.
• Consult a professional mechanic if unsure about repairs.
Check if emission-related components are covered under the vehicle's warranty.
This code has been more common in vehicles with aging secondary air injection systems.
Moderate – While it may not affect immediate drivability, it can lead to increased emissions and potential engine performance issues.
Driving with this code may lead to failing emissions tests and could be illegal in areas with strict emissions regulations.
• Engine at operating temperature
• Secondary air injection system active
The secondary air injection system components are typically located near the front of the engine bay, including the air pump and associated hoses.
Q: Can I drive my car with a P0492 code?
A: You can drive the car, but it's best to fix the issue soon to avoid emissions problems.
Q: Will a P0492 code cause my car to fail an emissions test?
A: Yes, a P0492 code can cause your car to fail an emissions test due to increased emissions.
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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.