The hot car method in winter must be correct.
The winter is over, and it is necessary to preheat the vehicle before driving on the road. This is common knowledge that drivers know. Many people think that after the ignition is started, they should walk in the same place for a while and then walk for more insurance. Some people think that today's cars are not so spoiled and do not need to deliberately heat the car. It is no big problem to drive immediately.
So how should the hot car be properly heated in winter? After reading the following instructions patiently, you may understand:
1. Why do you want a hot car?
Winter hot cars are especially necessary for car owners in the north.
Many people know that they want a hot car, but they don't know why they want a hot car. In fact, the main reason for the hot car is that after the car is parked for a long time, the engine oil in the engine flows back into the oil pan of the lower part of the engine. Therefore, after ignition, the upper part of the engine is in a state of lack of lubrication of the oil, about 30 seconds after the start of the engine, the oil will be transported to the piston and connecting rod which need lubrication most in the engine due to the operation of the oil pump. Parts such as crankshafts.
2, the car will be harmful
I don't know if you noticed: we usually find that when the vehicle is started, the tachometer pointer will be at least twice as high as the normal idle speed (the automatic transmission is more obvious). This is when the vehicle is ignited, the computer automatic control module (commonly known as ECU) on the modern car allows the fuel injection system to spray some fuel into the cylinder to increase the engine speed so that it can heat up quickly in the cold state. As for the degree to which the cold car speed rises, depending on the external ambient temperature and ECU settings of each car, not every car will have the same speed value.
Under normal circumstances, the engine speed will drop significantly within one minute of the cold start, so if you don't want to wait for this short one minute, the big foot will go away. That is undoubtedly aggravating the wear and tear of the engine parts, which may not cause serious problems in a short period of time, but in the long run, the engine will be "long-lived".
After the vehicle is started, the lubricating oil is not supplied in place at the time of idling, so wear is most likely to occur.
According to statistics, the wear of the engine parts is more than 90%, which is caused within three minutes after the cold car is started. Therefore, in winter, especially in the cold winter, the in-situ idle hot car is very easy to damage the engine. It is recommended that the owner adopt a low-speed slow driving method.
3, in-situ idle hot car is not desirable
Some people may say: Since the car can't be driven immediately after driving in the winter, then the car will be idling first, and the engine speed will fall back to the normal level. After the water temperature index is up, it is better to drive again. The hot car does make the engine fully warm up, but there are no small side effects.
Car maintenance experts said that the winter temperature is lower, hot cars are necessary, but most car owners think that early or long time no car, after starting the car, to idle the original hot car, wait for three or five minutes and then go on the road to the best.
The correct method of hot car should be to take the road after starting for one minute, but do not drive at high speed at this time, should keep at low speed, the engine speed should not exceed 3000 rpm, generally maintain 2000 rpm, otherwise the engine and The intense wear on the gearbox is irreversible. After the engine temperature rises to the normal operating temperature, resume normal driving.
4, the correct hot car method
After the start of winter, the water temperature will be lower than the normal temperature, and it will be gradually accelerated after the water temperature is normal.
Wait a little while in the car after ignition (the waiting time depends on the relatively stable time after the speed drops, generally no more than one minute). For example, when the vehicle is just driving, the speed is above 2000 rpm. After about 30 seconds to 1 minute, the engine speedometer pointer drops to about 1200 rpm (but it has not dropped to the normal idle speed of 800 to 1000 rpm), and it has been basically stable. There is no obvious fluctuation, and the body has no obvious jitter. In this case, the gear can be started.
The following starting control of the two models is as follows:
For manual transmission models: It is recommended to hang the first gear without stepping on the throttle. At this time, the engine will run slowly for 3 to 5 minutes at low speed. If it is heavy truck or coming from the ramp of the underground garage, it may feel that the power is insufficient. Add some throttles (remember to lightly step on, the engine speed should not exceed 2000 rpm!), wait for the pointer of the water temperature meter to move up slightly, then add to the second gear (control the speed of 20 to 30 kilometers) slowly. The water temperature gauge pointer rises to nearly 60 ° C (more than one-third of the water temperature gauge), and the upshift can be accelerated step by step.
For the automatic transmission model: the viscosity of the oil in the automatic transmission in winter will become larger. When the oil pump starts working, many vehicles will have an upshift phenomenon. For example, the vehicle can automatically upshift at 2000 rpm. When the cold car starts to reach 3000 rpm or higher, it will go up. At this time, if the throttle is stepped deeply, it is extremely undesirable to rush to increase the engine speed to force an automatic upshift.
Driving on the road in winter, the engine speed is controlled within 2000 rpm just after the car is parked.
The automatic gear should be kept at 2,000 rpm for 3 to 5 minutes in the D gear. Generally, the automatic car with good condition, even if it does not step on the throttle, its low speed at idle speed is enough to make the vehicle move slowly forward (many veterans are It is by means of low speed walking at this time to heat the car, huh, this is a small trick). At this time, the automatic transmission will not be upshifted, the oil in the transmission will be fully circulated, and the viscosity of the oil will gradually return to normal. Similarly, when the water temperature indicator rises nearly 60 ° C (more than one-third of the water temperature gauge), it can accelerate normally.
It is worth reminding that if the automatic transmission car is often stepped on the accelerator when it is cold in winter, it will rise rapidly to 3000~4000 rpm to complete the automatic upshift, which will undoubtedly affect the clutch plates and brake pads in the automatic transmission, including the inside. The spool mechanism will cause some abnormal wear and will shorten the service life of the automatic transmission.
Summary: In fact, the winter hot car can be slightly different according to different models, different displacements, different loads, different climates, there is no uniform mode to follow, nor can it be hard to move. We only need to master an important principle - the winter hot car should be a dynamic process of steady warming and gradual acceleration. It is not advisable to idle for a long time in the original place. After the initial start, the low speed must be slowed down. Remember that there should be no premature deep stepping on the throttle, rapid acceleration, and sudden braking.