Idle Speed
Fuel Injection System
For all Motronic fuel injection system component locations.
For all Motronic fuel injection system removal/installation procedures and torque specifications.
• All manufacturers special tools as well as common tools may contain a manufacturer specific part number. These tools may be substituted with an equivalent aftermarket tool or are available for purchase through Audi.
• Manufacturers special tools as well as common tools that contain a manufacturer specific part number may be referenced in the test procedure illustrations showing the tool use or installation. If the manufacturer specific tool is not being used, an equivalent aftermarket tool may be installed in the same manner as the manufacturers special tool.
• The manufacturers test box Test Box 105 Pin (VAG1598/42) is available for purchase or rental.
Observe Safety Precautions
Observe Clean Working Conditions
Observe Technical Data
Safety Precautions
To reduce the risk of personal injury and/or damage to the fuel injection and ignition system. Note the following:
The fuel system is pressurized. Before loosening hose connections or opening the test connection (to measure fuel pressure), place a cloth around the connection. Then release pressure by carefully loosening the connection.
• Always switch off ignition before disconnecting or connecting lines of the fuel injection and ignition system, including test leads.
• During some of the tests, a Diagnostic Trouble Code (DTC) may be recognized and stored by the control module. At the end of all tests and repairs, the DTC memory should be checked and, if necessary, erased. After erasing the DTC memory, a readiness code must be generated for the engine control module.
• Always switch ignition off before cleaning engine.
• The battery must only be disconnected and connected with the ignition switched off, since the Engine Control Module (ECM) can otherwise be damaged.
• Observe procedures for disconnecting battery.
Observe the following if test and measuring instruments are required during a test drive:
• Test and measuring equipment must always be secured to the rear seat and be operated from there by a second person.
• If test and measuring instruments are operated from the front passenger's seat and the vehicle is involved in an accident, there is a possibility that the person sitting in this seat may receive serious injuries when the airbag is deployed.
The use of nails, paper clips, or another unauthorized materials to back-probe electrical harness connectors is strictly prohibited and may cause damage to the electrical harness connectors, terminal ends or damage to a component. Use only the manufacturers test lead kit or an equivalent aftermarket test lead kit for back-probing all electrical harness connectors.
Clean Working Conditions
Even minor contaminations can lead to malfunctions in the fuel injection system. When working on the fuel supply/injection system, pay careful attention to the following Clean Working Conditions:
• Thoroughly clean all unions and adjacent areas with engine or brake cleaner and dry before disconnecting.
• Plug open lines and connections immediately with appropriate protective caps.
• Place removed parts on a clean surface and cover. Use lint-free cloths.
• Install clean components: Remove replacement parts immediately prior to installation. Do not use parts that have been stored unpacked (e.g. in tool boxes etc.).
• When the system is open: Do not work with compressed air. Do not move vehicle unless absolutely necessary.
• Separated electrical connectors: Protect from dirt and moisture. Make sure connections are dry when reconnecting.
Technical Data
