Fuel Delivery and Air Induction: Description and Operation

Fuel Injection, General Information


NOTE:
- The Engine Control Module (ECM) has On Board Diagnostic (OBD) capability. Before carrying out repairs and troubleshooting check the DTC memories of all control modules must be checked using the automatic test sequence. This is necessary as various control modules are connected to each other via a CAN-Bus. The vacuum hoses and connections must also be checked (unmetered air).
- Fuel hoses in engine compartment must only be secured with spring type clips. The use of clamp or screw type clips is not permissible.
- Disconnecting the battery must only be done with the ignition switched off. If the radio is coded, obtain code before disconnecting the battery.
- Components marked with * are checked via the On Board Diagnostic (OBD).
- Components marked with ** can be checked with the Output Diagnostic Test Mode (DTM).
- For trouble-free operation of the electrical components, a voltage of at least 11.5 V is necessary.
- Do not use sealants containing silicone. Particles of silicone drawn into the engine, will not be burnt in the engine and damage the oxygen sensor.
- If the engine starts, runs for a short period and then stops, after diagnosis, repairs or component tests, then the malfunction may lie with the immobilizer which is blocking the engine control module. The DTC memory must be checked and if necessary the control module adapted.
- During some checks it is possible that the control module will recognize and store a DTC. Therefore after completing all checks and repairs the Diagnostic Trouble Code (DTC) memory must be checked and if necessary erased.
- Vehicles with an airbag are fitted with a crash/fuel shut-off. It reduces the risk of a vehicle burning in the event of a crash in that the fuel pump is switched off by the fuel pump relay.
- When driver's door is opened, the fuel pump is activated for 2 seconds so that pressure can build-up in the fuel system. Thus a better starting behavior is obtained.

Safety precautions. Refer to "Fuel Injector" Technician Safety Information

Rules for cleanliness. Refer to "Fuel Injector" Vehicle Damage Warnings