1 - fuel tank; 2 - fuel pump; 3 - fuel filter; 4 - fuel pressure regulator; 5 - adsorber; 6 - ECU; 7 - camshaft position sensor; 8 - ignition coil; 9 - spark plug; 10 - nozzle; 11 - adsorber valve; 12 - air temperature sensor; 13 - air flow meter; 14 - oxygen content sensor; 15 - coolant temperature sensor; 16 - knock sensor; 17 - throttle position sensor; 18 - idle speed regulator; 19, 20 - to AL diagnostics; 21 - engine shaft speed sensor; 22 - AB; 23 - ignition switch; 24 - turning on the air conditioner
The sequence of checks when determining malfunctions of the CMCD «Motronic» (DME)
Symptom | Check sequence |
Engine won't start | 1. Connection with «weight» engine and battery 2. Fuses, fuel pump, relay 3. Fuel filter and fuel pump 4. Tightness of the air path 5. Electrical wiring and connections of the fuel injection subsystem 6. Nozzles 7. Air flow meter 8. Fuel pressure regulator and fuel pump performance 9. ECU and reliability of connections in its connector |
1. Connection with «weight» engine and battery 2. Fuses, fuel pump, relay 3. Fuel filter and fuel pump 4. Tightness of the air path 5. Coolant temperature sensor 6. Idle speed regulator 7. Air flow meter filter 8. Air flow meter 9. Fuel pressure regulator and fuel pump performance 10. Nozzles 11. Throttle body, throttle body, throttle sticking 12. Electrical wiring and connections of the fuel injection subsystem 13. ECU and reliability of connections in its connector | |
1. Connection with «weight» engine and battery 2. Fuses, fuel pump, injection system relay 3. Fuel filter and fuel pump 4. Tightness of the air path 5. Electrical wiring and connections of the fuel injection system 6. Air flow meter 7. Coolant temperature sensor 8. Fuel pressure regulator and fuel pump performance 9. Nozzles 10. Air flow meter filter 11. ECU and reliability of connections in its connector 12. Knock prevention system | |
Engine starts and stalls | 1. Connection with «weight» engine and battery 2. Fuses, fuel pump, injection system relay 3. Fuel filter and fuel pump 4. Tightness of the air path 5. Electrical wiring and connections of the fuel injection subsystem 6. Idle speed regulator 7. Throttle valve, throttle body, throttle valve stuck, ajar 8. Air flow meter filter 9. Air flow meter 10. Fuel pressure regulator and fuel pump performance 11. Nozzles 12. ECU and the reliability of the connection in its connector |
Unstable engine idling | 1. Idle speed regulator 2. Tightness of the air path 3. Ground connection» engine and battery 4. Electrical wiring and connections of the fuel injection subsystem 5. Throttle body, throttle body, throttle sticking, opening 6. Coolant temperature sensor 7. Air flow meter filter 8. Air flow meter 9. Fuel pressure regulator and fuel pump performance 10. Nozzles 11. ECU and reliability of connections in its connector |
Idle speed not correct | 1. Tightness of the air path 2. Connection with «weight» engine and battery 3. Electrical wiring and connections of the fuel injection subsystem 4. Idle speed regulator 5. Throttle position sensor 6. Air flow meter filter 7. Air flow meter 8. Coolant temperature sensor 9. Throttle valve, throttle body, throttle valve stuck, ajar 10. Nozzles 11. ECU and reliability of connections in its connector |
Ignition misfires at idle | 1. Tightness of the air path 2. Coolant temperature sensor 3. Air flow meter filter 4. Air flow meter 5. Connection with «weight» engine and battery 6. Wiring and connections of the injection subsystem 7. Nozzles 8. ECU and the reliability of the connections in its connector |
Misfiring while driving at a constant speed | Air flow meter |
Interruptions in the engine during acceleration | 1. Tightness of the air path 2. Connection with «weight» engine and battery 3. Electrical wiring and connections of the fuel injection subsystem 4. Air flow meter filter 5. Air flow meter 6. Coolant temperature sensor 7. Fuel filter and fuel pump 6. Fuel pressure regulator and fuel pump performance 9. Nozzles 10. Exhaust oxygen concentration sensor (depending on configuration) 11. ECU and reliability of connections in its connector |
Unstable operation of the engine at a constant speed | 1. Tightness of the air path 2. Connection with «weight» engine and battery 3. Electrical wiring and connections of the fuel injection subsystem 4. Air flow meter filter 5. Air flow meter 6. Coolant temperature sensor 7. Fuel filter and fuel pump 8. Fuel pressure regulator and fuel pump performance 9. Nozzles 10. ECU and reliability of connections in its connector |
Unstable operation of the engine during engine braking | 1. Connection with «weight» engine and battery 2. Wiring and connections of the injection subsystem 3. Coolant temperature sensor 4. Fuses, fuel pump, injection system relay 5. Throttle position sensor 6. Nozzles 7. Air flow meter 8. Knock prevention system 9. ECU and reliability of connections in its connector |
Detonation during acceleration | 1. Knock prevention system 2. Wiring and connections of the injection subsystem 3. Air flow meter 4. ECU and the reliability of the connections in its connector |
Poor engine response | 1. Tightness of the air path 2. Connection with «weight» engine and battery 3. Electrical wiring and connections of the fuel injection subsystem 4. Throttle position sensor 5. Coolant temperature sensor 6. Fuel filter and fuel pump 7. Air flow meter filter 8. Air flow meter 9. Fuel pressure regulator and fuel pump performance 10. Nozzles 11. ECU and reliability of connections in its connector |
Increased fuel consumption | 1. Air flow meter filter 2. Emission control and exhaust gas recirculation valve 3. Coolant temperature sensor 4. Throttle position sensor 5. Idle speed regulator 6. Electrical wiring and connections of the fuel injection subsystem 7. Air flow meter 8. Nozzles 9. ECU and reliability of connections in its connector 10. Protection and partial load switches |
Increased CO content in exhaust gases | 1. Air flow meter filter 2. Exhaust oxygen concentration sensor (depending on configuration) 3. Emission control and exhaust gas recirculation valve 4. Throttle, throttle body, throttle sticking, opening 5. Throttle position sensor 6. Coolant temperature sensor 7. Connection with «weight» engine and battery 8. Wiring and connections of the injection subsystem 8. Nozzles 10. Air flow meter 11. ECU and reliability of connections in its connector |
Reduced CO content in exhaust gases | 1. Tightness of the air path 2. Exhaust oxygen concentration sensor (depending on configuration) 3. Emission control and exhaust gas recirculation valve (depending on configuration) 4. Air flow meter filter 5. Throttle position sensor 6. Coolant temperature sensor 7. Fuel filter and fuel pump 8. Fuel pressure regulator and fuel pump performance 9. Nozzles 10. Air flow meter 11. Wiring and connections of the injection subsystem 12. ECU and reliability of connections in its connector |
The engine does not develop full power and does not have sufficient throttle response | 1. Tightness of the air path 2. Air flow meter filter 3. Connection with «weight» engine and battery 4. Wiring and connections of the injection subsystem 5. Fuel filter and fuel pump 6. Coolant temperature sensor 7. Throttle position sensor 8. Air flow meter 9. Fuel pressure regulator and fuel pump performance 10. Nozzles 11. Exhaust oxygen concentration sensor (depending on configuration) 12. Throttle valve, throttle body, throttle valve sticking, its ajar 13. ECU and reliability of connections in its connector |