The car started moving without any problems
1. Before starting to move, you must fasten your seat belt.
2. Always try to start moving smoothly, since while the car is at minimum speed, the load on all elements of the transmission and chassis is maximum. Therefore, to prevent premature wear, it is necessary:
- a) If the car has an automatic transmission, do not press the accelerator pedal sharply.
- b) If the car has a manual transmission, do not release the clutch pedal abruptly. When starting to move, do not hold the clutch pedal for a long time.
- c) Do not make a sharp start with the steering wheels fully turned. If the car is front-wheel drive, this can damage the boot and/or CV joint (constant velocity joint), overloading it unnecessarily.
- d) If you are starting to move downhill, it is recommended to use the parking brake (in some cases, modern cars are equipped with hill start assist systems).
Jerks when starting the car
1. Malfunction of the fuel system and air intake system (see chapter "Power supply system" and "Intake and exhaust system").
2. Clutch failure (manual transmission) (see chapter "Clutch"). If the clutch slips when starting to move, this indicates excessive wear or a violation of the free and working travel adjustments of the clutch pedal. When the clutch slips, a characteristic smell of friction materials from the driven clutch disc may be emitted (this smell can also appear even if the clutch is working properly, if you keep the clutch pedal half-pressed for a long time, even when starting to move).
3. Violation of the valve timing installation (see above) (see chapter "Mechanical part of the engine"). In this case, it is possible to turn on the alarm "CHECK ENGINE"
4. Malfunction of the cardan transmission as a whole (see chapter "Drive shafts"), its increased wear (vehicles with a manual transmission and drive on both axles or only on the rear). Repairs should be carried out exclusively at a service station. There may be no jerking, but a dull metallic thud will be heard when driving off (basically it's two hits), then with each gear change.
5. Malfunction in the engine management system or in the transmission control system (cars with automatic transmission). In this case, it is possible to turn on the alarm "CHECK ENGINE" and/or a message will appear on the on-board computer screen (if the car is equipped). You should contact a service station immediately.
6. Detonation in engine cylinders (gasoline only). The most common cause of detonation is poor quality fuel. In this case, a characteristic metallic knock will be heard from the engine. It is necessary to change the place where you regularly fill up your car or switch to a higher quality fuel. Constant detonation is very harmful to the engine and can lead to failure or damage to the connecting rod-piston group and crankshaft, so do not delay in identifying the cause of this malfunction and eliminating it as soon as possible.
However, it is worth considering the fact that during or at the beginning of movement, when the throttle valve is sharply opened for maximum acceleration, detonation knocks may appear for 1-2 seconds; this is not a malfunction. In this case, the cause is a sharp change in the ignition timing (to an earlier one) to optimize engine operating processes and complete combustion of fuel.