AV-SCANNER / Service function guides / Fuel and emissions
This guide covers the complete process of removing carbon deposits from the intake system of direct injection engines, a service that has become routine as more vehicles adopt gasoline direct injection (GDI) technology. It is written for working mechanics and experienced DIYers who already understand engine fundamentals and are comfortable working around fuel and electrical systems. You will learn how carbon builds up, how to diagnose the symptoms, how to prepare the vehicle and workspace, and how to perform both chemical and mechanical cleaning methods safely. By the end, you will be able to execute the procedure from start to finish, verify the results with measurable data, and advise customers on aftercare to prevent recurrence.
Guidance is general and covers many makes. Exact procedures and values vary by model, so confirm them in the factory service information for your vehicle.
Download all 12 sections as a branded PDF to use in the workshop.
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