MULTIPORT Fuel Injection (MFI) - 4.2L V8 (AKB, Aux, AYS)

• Multiport Fuel Injection (MFI)
  • Motronic Multiport Fuel Injection (MFI) system, servicing
    • Safety precautions
    • Rules for cleanliness
    • Technical data (A8 vehicles)
    • Technical data (S8 vehicles)
    • Component locations, overview
    • Wiring and component check with VAG1598/31 test box
      • Notes
      • Connecting VAG1598/31 test box
    • Motronic Engine Control Module (ECM) -J220- (without metal anti -theft housing), replacing
      • Notes
      • Removing Engine Control Module (ECM)
      • Installing engine control module
    • Motronic Engine Control Module (ECM) -J220- (with metal anti -theft housing), replacing
      • Notes
      • Remove Engine Control Module (ECM)
        • Removing
      • Procedure:
      • Installing Engine Control Module (ECM)
  • Motronic Engine Control Module (ECM) Power Supply Relay -J271-, checking
    • Notes
    • Checking activation of the ECM power supply relay
    • Activating Cruise Control System (CCS)
    • Idle speed, checking
      • Test conditions
      • Checking idle speed
      • If the idle speed is too high or too low, or if the engine does not idle smoothly, and there are no malfunctions stored in the DTC memory, perform the following tests (marked with dots):
      • Relevance of figures in 5-digit readout in Display Group 056
    • Fuel pressure regulator and residual fuel pressure, checking
      • Requirements
    • Fuel injection volume, fuel injector leakage and spray pattern of injectors, checking
      • Test conditions
      • Removing fuel rail
      • Checking fuel injectors for leaks
      • Checking fuel injection volume
    • Fuel injectors, checking
      • Electrical testing of fuel injectors
      • Checking voltage supply
      • Checking wiring connections
    • Fuel Pump (FP) relay -J17- and relay activation, checking
      • Notes
      • Test conditions
      • Functional test of fuel pump relay
      • Testing activation of fuel pump relay
      • Checking activation for fuel pump and components
    • Mass Air Flow (MAF) sensor -G70-, checking
      • Requirements
      • Checking function
        • Notes
        • Reading Display Group 002
      • Checking voltage supply to MAF sensor
      • Checking Ground (GND) connection
      • Checking wiring for MAF sensor
    • Intake Air Temperature (IAT) sensor -G42-, checking
      • Notes
      • Checking wiring
    • Engine Coolant Temperature (ECT) sensor -G62-, checking
      • Notes
      • Testing wiring
  • Oxygen sensor control, checking
    • Oxygen sensor control, function
    • Oxygen sensor and oxygen sensor control before Three Way Catalytic Converter (TWC), checking
      • Special tools and equipment
      • Test conditions
      • Checking function
      • Significance of 3 digit indication in Display Group 30
      • Checking oxygen sensor adaptation and oxygen sensor control
        • Notes
        • Evaluation display group 32
        • Evaluation display group 33
    • Oxygen sensors aging, oxygen sensor before catalytic converter, checking
      • Test requirements
      • Test sequence for oxygen sensor 1 before catalytic converter bank 1
      • Continuation
      • Test sequence for oxygen sensor 1 before catalytic converter bank 2
    • Oxygen sensor and oxygen sensor control behind catalytic converter, checking
      • Test equipment and shop tools
        • Notes
        • Component location of connectors for oxygen sensors 2 behind catalytic converter:
      • Test conditions
      • Significance of 3 digit indication in Display Group 30
      • Checking oxygen sensor control behind catalytic converter
        • Notes
        • Evaluation display group 037 and 038
      • Continuation
    • Oxygen sensor heater for oxygen sensor, checking
      • Notes
      • Checking voltage supply for oxygen sensor heater
    • Oxygen sensor signal wire and activation, checking
      • Notes
      • Checking oxygen sensor wiring for Heated Oxygen Sensor (HO2S) -G39-
    • Checking wiring for Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130 -
      • Notes
      • Checking wiring for Heated Oxygen Sensor (HO2S) 2 -G108-
      • Checking wiring for Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131 -
    • Oxygen sensors, removing and installing
      • Removing
  • Intake manifold change-over, checking (A8 vehicles)
    • Notes
    • Intake manifold change-over, checking function
    • Intake Manifold Change -Over Valve -N156- and Intake Manifold Tuning (IMT) Valve -2- -N261-, checking
      • Notes
      • Checking voltage supply to intake manifold change-over valve
      • Checking activation of intake manifold change-over valve
      • Check wiring
    • Vacuum system, checking
      • Checking solenoid valves for obstructions and leaks
      • Checking vacuum system for leaks
  • Intake manifold change-over, checking (S8 vehicles)
    • Intake manifold change -over valve, checking function
    • Intake manifold change-over valve - N156-, checking
      • Notes
      • Checking voltage supply of intake manifold change-over valve
      • Checking activation of intake manifold change-over valve
      • Checking wire connection
    • Vacuum system, checking
      • Checking solenoid valve for throughput and proper seal
      • Checking vacuum system for proper seal
  • Evaporative Emission (EVAP) system, checking
    • Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-, checking
      • Checking for leaks
      • Electrical testing of Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-
      • Checking power supply to solenoid valve
      • Testing activation of Evaporative Emission (EVAP) Canister Purge Regulator Valve
    • Secondary Air Injection (AIR) Solenoid Valve -N112-, checking
    • Secondary Air Injection (AIR) pump relay -J299-, checking
      • Notes
      • Checking voltage supply for secondary air pump relay
      • Check activation of secondary air injection pump relay
    • Electronic Engine Power Control (EPC) warning light, checking
      • Electronic throttle system, function
    • Throttle valve control module -J338-, checking
    • Throttle valve control module, adaptation
      • Notes
      • Test conditions for adaptation of throttle valve control module
      • Throttle valve control module, adaptation notes
    • Angle sensor -1- for throttle drive (power accelerator actuation) -G187- and angle sensor -2- for throttle drive (power accelerator actuation) -G188-, checking
      • Notes
      • Checking voltage supply to throttle valve control module
      • Checking wiring for voltage, signal and activation
    • Electronic Engine Power Control (EPC) warning light in instrument cluster, significance
      • Notes
      • Checking function of warning light
    • Throttle Position (TP) sensor -G79- and sender -2- for accelerator pedal position -G185-, checking
      • Notes
      • Checking voltage supply of accelerator position sensors
      • Checking signal wiring and wiring connections between accelerator position sensors and engine control module
    • Brake light switch -F- and brake pedal switch -F47-, checking
      • Notes
      • Relevance of figures in 4-digit readout in display field 2
      • Checking voltage supply
      • Checking wiring connections
    • Additional signals, checking
      • Engine speed (RPM) signal, checking
    • A/C compressor shut-off, checking
      • Notes
      • Test conditions
  • Crash signal, checking
    • Notes
    • Engine mounts, checking
      • Notes
      • Checking voltage supply for engine mounts
      • Checking activation for engine mounts
      • Checking wiring connection
    • Data exchange between Engine Control Module (ECM), ABS/EDL control module, Transmission Control Module (TCM) or instrument cluster, checking
      • Notes
      • Checking bus system
      • Automatic Test Sequence
      • Checking two-wire bus system