Self Study Program 439 – Audi 2.0L TFSI flexible fuel engine

VAG SSP 439. In this Self Study Programme you will learn about the technology of the 2.0l TFSI flexible fuel engine and the differences between this engine and the basic 2.0l TFSI engine.

The 2.0l flexible fuel engine sees Audi making another contribution to environmental conservation. Audi has been offering this ethanol-compatible flexible fuel engine with European Audi A4 models since the autumn of 2009. Today bioethanol is produced via alcoholic fermentation of energy crops such as wheat, maize and sugar cane. Thanks to the high renewable factor, the CO2 balance of bioethanol in the vehicle as a whole is up to 75 % more favourable than that of conventional petroleum-based fuel.

The advantage of the Audi concept is that the engine can be run on fuel with any concentration of up to 85 % ethanol with no noticeable differences in drivability or performance.

Political goals of the international community in marketing bioethanol are:

  • To drastically reduce greenhouse gas emissions.
  • To reduce the dependency on imported fossil fuels.
  • In terms of agricultural policy, it is envisaged that bioethanol will provide alternative sources of income and development opportunities for agriculture.
  • In terms of trade policy, intensive production of biofuels will help to curb agricultural overproduction and, thus, reduce subsidy levels.

Objectives for the development of the 2.0l TFSI flexible fuel engine are:

  • To use an existing basic engine; 2.0l TFSI flexible fuel engine designed to run on ethanol is based on the existing 2.0l TFSI engine with AVS* and start-stop technology.
  • From the start, the customer does not notice any drawbacks in terms of driving comfort or driving pleasure.
  • An engine running on bioethanol should start reliably at low ambient temperatures without any need for pre-heating, which is usually the case with competitor products today.
  • The favourable properties of the bioethanol will be utilised to optimise engine efficiency at all operating points.

Learning objectives of this Self Study Programme are:

If you have worked your way through this Self Study Programme, you will be able to answer the following questions:

  • What does the term “bioethanol” mean?
  • What modifications does the 2.0l TFSI flexible fuel engine have compared to the basic engine?
  • What modifications have been made to the fuel system?
  • What are the special features of the engine management system?
  • What are the points to note when servicing the vehicle?


  • Introduction
    • Brief technical description
    • Specifi cations
  • Bioethanol
    • Basic information
    • Specifi cations for bioethanol
    • Comparison of fuel properties
    • Why E85, and not pure alcohol?
    • Production process
  • Modifi cations to the basic engine
    • Development goals
    • Cylinder liners
    • Cylinder head
    • Cranktrain
    • Conrod
  • Fuel system
    • Introduction
    • Fuel quality sender G446
  • Engine management
    • Overview of the Bosch MED 17.1 system
    • Cold starting
    • Cold starting with ethanol
    • Fuel ingress into the engine oil and fuel extraction from the engine oil
  • Service
    • Scope of maintenance
    • Control and auxiliary drive
  • Annex
    • Glossary
  • Test your knowledge
    • Summary
    • Self Study Programmes

The Self Study Programme explains the basics of the design and function of new models, new automotive components or new technologies. It is not a Repair Manual! Figures given are for explanatory purposes only and refer to the software version valid at the time of preparation of the SSP.
For maintenance and repair work, always refer to the current technical literature. Terms shown in italics and marked by an asterisk 20943 are explained in the glossary at the back of this Self Study Programme.

Language: English
Format: PDF
Pages: 32

Self Study Program 439 – Audi 2.0l TFSI flexible fuel engine PDF free online