1. Engine malfunction - decreased compression in one or more cylinders, change in valve timing when the camshaft drive belt jumps, additional air is sucked into the engine intake tract. Coking of the exhaust system or damage to the exhaust gas neutralizer.
2. Malfunction of the engine fuel system - clogged injectors and fuel filter, fuel supply system hoses. Insufficient fuel pump supply. Use of low-quality fuel.
3. Malfunction of the ignition system - failure of the spark plug, breakdown of the high-voltage circuit of the system.
4. Malfunction of the engine management system - failure of the system sensors. If any sensor fails, the electronic control unit switches to a backup program, which allows you to get to a garage or car service center, but the engine's power and economic characteristics are reduced in this case. 5. Clutch slippage due to wear or misalignment.
6. Malfunction of the braking system - braking of one or more wheels when the vehicle is moving, incorrect adjustment of the parking brake.
7. Insufficient air pressure in the tires - tire inflation required.
8. Overloading the vehicle.
A complete computer diagnostics of a car should be carried out by highly qualified specialists using special diagnostic equipment, so contact a car service.
You can carry out the following repairs yourself.
1. Check and adjust the air pressure in your tires to the correct level.
2. Check the operation of the service brake system and the parking brake. It is not necessary to remove the wheels for this. Find a flat section of road and, in dry, windless weather, conduct a test run to determine the vehicle's coasting. The car must be fully fueled and only the driver must be in the car. Accelerate the car to 50 km/h, level off the speed, then turn off the gear and coast until it comes to a complete stop. Perform another run in the opposite direction. The run-out should be about 500 m.
3. Check the operation of the ignition system as described above.
4. Check the operation of the clutch. The initial check is carried out on a level area free of obstacles. Set the idle speed to a high value using the accelerator pedal - approximately 1500 rpm. Apply the parking brake to the vehicle. Depress the clutch and engage first gear. Then begin to slowly release the clutch pedal. If the engine stalls, the clutch is working properly and is not slipping. If the engine does not stall, the clutch is worn out and needs to be replaced. The clutch drive cannot be adjusted (wear is automatically compensated by a device on the drive cable).