Fuel Delivery and Air Induction: Description and Operation

General Notes On Injection

- The engine control module is equipped with On Board Diagnostic (OBD). Before performing repairs and troubleshooting the Diagnostic Trouble Code (DTC) memory of all control modules must be interrogated using the automatic test sequence (in Guided fault finding). This is necessary as the various control modules are interconnected via a data bus. Also the vacuum hoses and connections must be checked (unmetered air).

- Fuel hoses in the engine compartment must only be secured with spring-type clips. The use of clamp or screw-type clips is not permitted.

- The battery may only be disconnected when the ignition is switched off. If a coded radio is installed, obtain the radio code before disconnecting the battery.

- For trouble-free operation of the electrical components, a voltage of at least 11.5 V is necessary.

- Do not use sealing compounds containing silicone. Particles of silicone drawn into the engine will not be burned in the engine and cause damage to the oxygen sensors.

- If the engine starts, runs for a short period and then stops, after troubleshooting, repairs or component tests, then the cause may be the immobilizer blocking the engine control module. In such cases the control module must be adapted; Adapting components.

- During some checks it is possible that the control module will detect and store a fault. Therefore after completing all checks and repairs the DTC memory must be interrogated and if necessary erased., Interrogating and erasing DTC memory.

- Vehicles with an airbag are equipped with a crash fuel shut-off system. This system reduces the danger of a fire in a crash in that the fuel pump is switched off via the fuel pump relay.

- When the door is opened the fuel pump is activated for 2 seconds to build up pressure in fuel system. This improves the starting characteristics of the engine.



General Notes On Fuel Injection

NOTE:
- The Engine Control Module (ECM) is equipped with On Board Diagnostic (OBD). Always check DTC memory first, before performing repairs or troubleshooting. Vacuum hoses and connections should also be checked (false air).
- For the electric components to work properly, a voltage of at least 11.5 V is required.
- Do not use any silicone sealant. Traces of silicone components which are sucked into the engine are not burned there, and they damage the oxygen sensor.
- The battery must only be disconnected and connected with the ignition switched off, since the Engine Control Module (ECM) can otherwise be damaged.
- Fuel hoses at engine must only be secured with spring-type clamps. The use of clamping collars or screw clamps is not permitted.







- VAS 5024A spring clip installation tool is recommended for installing spring-type clips.
- Components marked with * are tested via On Board Diagnostic (OBD), Diagnostic mode 3: Check DTC memory.
- It is possible that the control module will recognize a malfunction and store a DTC during some tests. Therefore the following work steps must be performed in the mentioned sequence after ending all tests and repairs.