While the car is moving, various unexpected problems with engine operation may arise, manifested in instability of speed or sudden shutdown of the engine at the most inopportune moment.

Experts from the njcar.ru portal identified the most common causes of such problems and provided recommendations on actions in such situations.

Ideally, when the engine is warm, the tachometer needle should be kept in the range from 800 to 1000 rpm without changes. If deviations are noticed, such as fluctuations from 500 to 1500 rpm, this may indicate a malfunction in the engine.

One of the common reasons for engine speed instability is the use of low-quality fuel when refueling a car. In such cases, the fuel injectors may become clogged and carbon deposits may form on the spark plugs.

The solution to this problem is usually replacing the spark plugs, cleaning the injectors and switching to using higher quality fuel.

There may also be problems with fuel supply due to a clogged fuel filter or a malfunction of the fuel pump. In such cases, it is recommended to replace the fuel filter or diagnose the fuel pump to restore normal engine operation.

Unstable engine speed and tripping can be caused by faulty high-voltage wires, spark plugs or ignition coils. The solution to this problem is to replace damaged components.

Also, one of the causes of these problems may be a malfunction of the exhaust gas recirculation (EGR) valve. If this problem is present, a sharp decrease in speed when braking or even a complete engine stop may occur. It is recommended to clean the valve or completely replace it to eliminate this problem.

Sometimes, unstable speed can indicate serious problems, such as a defect in the electronic engine control unit, a malfunction in the throttle position sensor, or a problem with the idle air control.

In such situations, it is recommended to contact a car service to identify and eliminate possible faults.