It's too cold, and the engine reports trouble.

The common faults of cold car under low temperature in winter are: it is not easy to start the cold car, the engine of the cold car is idling and the acceleration is poor. Let's analyze these failures.

1, the cold car is not easy to start.

According to the automobile repair standard, the engine should be started when the ambient temperature is above -5℃ and the starter is used for 5 s at most 3 times. With the improvement of automobile technology, many users have long rejected this standard. They hope that the starter can start successfully within 5 s, which modern electronically controlled engines can generally do. If the engine is difficult to start, the failure causes usually include

① Starting system failure, such as insufficient battery power, damaged starter or starter circuit failure.

② Mechanical failures of the engine, such as air leakage in the intake pipe, poor sealing between the piston and the cylinder, and lax valve closure, lead to low cylinder pressure.

③ There is too much carbon deposit on the back of the intake valve and intake pipe, which causes the injected gasoline to be adsorbed by carbon deposit and cannot enter the combustion chamber.

④ Engine management system failure, such as weak speed sensor signal, incorrect water temperature signal, poor line contact, etc.

⑤ There is something wrong with the ignition system, such as excessive carbon deposit in the spark plug or incorrect gap, high-voltage line leakage and damaged ignition coil.

⑥ Faults in the oil supply system, such as insufficient pressure in the fuel system, leakage or blockage of the fuel injector, etc.

2, cold car engine idling jitter

When the engine is cold-started, if the engine fails to idle quickly or the speed is unstable without cold-starting, the failure causes generally include:

① Mechanical failure of the engine, such as low pressure in each cylinder.

(2) air intake system failure, such as air intake pipe leakage, etc.

③ Excessive carbon deposition on the back of intake valve and intake pipe.

(4) Engine management system failure, such as incorrect water temperature and intake air temperature signals, line failure, etc.

⑤ There are faults in the ignition system, such as excessive carbon deposition in the spark plug or incorrect gap, leakage of high-voltage line and distributor cover, and damage to the ignition coil.

⑥ Faults in the oil supply system, such as too much colloidal carbon deposit in the injector, lead to the injector being closed loosely or blocked.

3, cold car acceleration car.

Although the operating instructions of many automobile manufacturers indicate that the cold car can be started without preheating, the author thinks that it is of great benefit to the engine if the engine can be warmed up for 3~5 min after starting. Because this can reduce the mechanical wear of the engine and make the starting power of the small displacement engine sufficient. If the cold car accelerates quickly after starting, there will be a slight collision. If the crash is serious, the failure causes are generally:

① Engine mechanical system failure, such as low cylinder pressure leading to engine power reduction, is more prominent in cold state.

② There are too many carbon deposits on the back of intake valve and intake pipe, which leads to the injected gasoline being adsorbed by carbon deposits and unable to enter the combustion chamber.

③ Engine management system failure, such as incorrect water temperature and intake air temperature signals, line failure, etc.

(4) there is something wrong with the ignition system, such as excessive carbon deposition on the spark plug or incorrect gap, leakage of the high-voltage line and distributor cover, and damage to the ignition coil.

⑤ Faults in the oil supply system, such as too much colloidal carbon deposit in the injector, lead to the injector being closed loosely or blocked.