Why is the fault light on in the Audi Q3?

[VonEliza]

Audi vehicles may experience an illuminated engine fault light due to reasons such as poor-quality air filters, dirty throttle bodies, severe engine carbon buildup, or potential issues with the high-pressure pump. Specific causes are as follows: Poor-quality air filters: If the engine shows no abnormal response and acceleration/deceleration are normal, the fault light may be triggered by factors like poor fuel quality, impurities in the fuel tank clogging the fuel filter, excessively dirty air filters, installation of low-quality air filters, dirty throttle bodies, or severe engine carbon buildup. High-pressure pump issues: When the engine fault light is on accompanied by symptoms like inability to accelerate, idle shaking, or even stalling, specialized diagnostic tools should be used to read engine system fault codes for targeted repairs. Common faulty components include non-firing spark plugs, open-circuit ignition coils, damaged fuel pumps, faulty fuel pump control units, or in direct-injection engines, potential high-pressure pump failures.