Fuel Delivery and Air Induction: Description and Operation

Fuel Injection system, general notes

- The Engine Control Module (ECM) is equipped with On board Diagnostic. Before carrying out repairs and Troubleshooting; DTC memory must be checked. Also check the vacuum hoses and connections for leaks or unmeasured air.
- Fuel hoses in engine compartment must only be secured with spring clips. The use of clamp or screw clips is not permissible.
- VAG 7927 pliers are recommended for installing spring clips.
- Disconnecting and connecting the battery must only be done with the ignition switched off, otherwise the Engine Control Module could be damaged.
- Components marked with * are checked via the On Board Diagnostic system.
- Components marked with ** can be checked via the Output Diagnostic Test Mode (DTM).
- For trouble-free operation of the electrical components, 11.5 Volts minimum is required.
- Do not use sealants containing silicone. Particles of silicone drawn into the engine, will not be burnt in the engine and can impair Oxygen sensor function.
- During some checks it is possible that the Control Module will recognise and store a malfunction. Therefore after completing all checks and repairs DTC memory must be checked and if necessary erased.