Troubleshooting
When troubleshooting an engine, start with a performance check and inspection of major systems. If the engine is malfunctioning, erratic idle speed, or insufficient acceleration, check the following main systems:
1. Power supply:
- battery;
- burnt jumper;
- fuse.
2. Connections with "weight"
3. Fuel supply:
- fuel line;
- fuel filter;
- fuel pump.
4. Ignition system:
- spark plug;
- high voltage wires;
- ignition coil.
5. System of decrease in toxicity of the fulfilled gases:
- crankcase ventilation system;
- vacuum leak.
6. Other:
- setting the ignition timing;
- idle speed.
Malfunctions of the MFI system are often caused by poor contacts in the wiring harness connectors. Therefore, check the reliability of the connection of all connectors.
Checking the idle speed
Warning! Before checking the idle speed, make sure that the spark plugs, fuel injectors, idle speed modulator (ISC), compression, etc. are in order.
Verification conditions
1. The engine must be warmed up to a coolant temperature of 80-95°C.
2. Headlights, side lighting, radiator fan and all consumers of electrical energy must be turned off.
3. The gearbox must be in neutral.
4. The steering wheel must be set to drive straight ahead.
Examination
1. Connect a tachometer to the primary winding of the ignition coil or a scanner to the diagnostic socket.
2. Start the engine and let it run at idle speed.
3. Increase the crankshaft speed to 2000-3000 min-1 for no more than 5 s, then let it idle for 2 minutes.
4. On the tachometer, determine the idle speed.