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 there is a leak in the air system that helps clean the car's exhaust on one side of the engine.
The secondary air injection system is designed to reduce emissions by injecting air into the exhaust stream. A leak in this system can lead to increased emissions and potential engine performance issues.
The P146D code indicates a detected leak in the secondary air injection system on bank 2 of the engine. This system is responsible for injecting fresh air into the exhaust to help burn off excess fuel and reduce emissions. A leak can disrupt this process, leading to inefficiency and increased emissions.
• Check engine light on
• Increased emissions
• Possible rough idle
• Cracked or damaged air hoses
• Faulty air pump
• Defective check valve
Secondary Air Injection: A system that injects air into the exhaust to reduce emissions.
Bank 2: Refers to the side of the engine opposite bank 1, typically the side without cylinder 1.
• Perform a visual inspection of the secondary air injection system hoses and connections.
• Use a smoke machine to detect leaks in the system.
• Check the operation of the air pump and check valve.
• Replace damaged or cracked air hoses.
• Repair or replace the faulty air pump.
• Replace the defective check valve.
• OBD-II scanner
• Smoke machine
• Basic hand tools
$150 - $500
Moderate
• BMW 3 Series
• Audi A4
• Mercedes-Benz C-Class
• Regular maintenance and inspection of the air injection system
• Replace hoses and components as needed
• Ensure proper operation of the air pump and valves
Emissions System Issue
• Address the issue promptly to avoid increased emissions.
• Consult a professional mechanic if unsure about repairs.
Check vehicle warranty for emissions-related repairs coverage.
This code has been associated with emissions system issues in vehicles with secondary air injection systems.
Moderate – While not immediately critical, addressing the issue will help maintain emissions standards and engine performance.
Ignoring emissions-related issues can lead to failing emissions tests and potential fines.
• Engine at operating temperature
• System under load
The secondary air injection system components are typically located near the exhaust manifold on the engine's bank 2 side.
Q: Can I drive with a P146D code?
A: While you can drive with this code, it's best to address it soon to avoid increased emissions and potential engine performance issues.
Q: How do I know if the secondary air injection system is working?
A: A functioning system will not trigger a check engine light related to air injection, and emissions will be within normal limits.
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