A statistic of automatic transmission maintenance shows that more than 90% of the wear of engine components is caused within 3 minutes after cold start. The main reasons for the need for hot cars are as follows.

1.發(fā)動(dòng)機(jī)剛剛啟動(dòng)時(shí)，供油系統(tǒng)溫度尚低，無(wú)法達(dá)到工作溫度(90~100攝氏度)，汽油不能全霧化，這時(shí)的汽油還處于液態(tài)，如果強(qiáng)行加速行駛，因?yàn)橛蜌饣旌媳冗^(guò)高，會(huì)令油耗升高、動(dòng)力不足，而且汽油燃燒也不好。

1. When the engine is just started, the temperature of the oil supply system is still low and cannot reach the working temperature (90 ~ 100 ℃), and the gasoline cannot be fully atomized. At this time, the gasoline is still in liquid state. If you forcibly accelerate the driving, because the fuel air mixing ratio is too high, the fuel consumption will increase, the power will be insufficient, and the gasoline combustion will be poor.

2.變速箱中的潤(rùn)滑油此時(shí)也都因重力作用，囤積在下方，這時(shí)如果把車開(kāi)不夠造成的。只有行車時(shí)讓變速箱齒輪運(yùn)轉(zhuǎn)起來(lái)，才能將所以根本達(dá)不到潤(rùn)底部潤(rùn)滑油帶起，潤(rùn)滑上部。如果只在原地用怠速熱車，由于變速箱沒(méi)有油泵，所以根本達(dá)不到潤(rùn)滑作用。

2. The lubricating oil in the gearbox is also stored under the action of gravity. At this time, it will be caused if the car is not driven enough. Only when the transmission gear is operated during driving can the lubricating oil at the bottom which can not be lubricated at all be brought up to lubricate the upper part. If you only use idle speed to warm up the car in place, the lubrication effect can not be achieved because there is no oil pump in the transmission.

3.車輛在經(jīng)過(guò)長(zhǎng)時(shí)間停放后，發(fā)動(dòng)機(jī)內(nèi)的機(jī)油會(huì)集中在下方油底殼內(nèi)，各部件表面的潤(rùn)滑油膜基本上已經(jīng)消失，這時(shí)啟動(dòng)發(fā)動(dòng)機(jī)，其上半部分是沒(méi)有機(jī)油的，需要大約30秒的時(shí)間，機(jī)油泵才能將機(jī)油輸送到發(fā)動(dòng)機(jī)活塞、連桿和曲軸等需要潤(rùn)滑的部件。

3. After the vehicle is parked for a long time, the oil in the engine will be concentrated in the lower oil pan, and the lubricating oil film on the surface of each component has basically disappeared. At this time, when the engine is started, the upper part of the engine is free of oil, and it takes about 30 seconds for the oil pump to deliver the oil to the engine piston, connecting rod, crankshaft and other components that need lubrication.

現(xiàn)在的汽車一般都使用電子噴油嘴，不同于老式的化油器車型，電噴車供油系統(tǒng)由ECU控制，不受空氣流速和溫度的影響，燃油霧化程度高，發(fā)動(dòng)機(jī)啟動(dòng)后很短時(shí)間內(nèi)就可以達(dá)到穩(wěn)定的怠速。所以熱車無(wú)需時(shí)間太長(zhǎng)，只要機(jī)油壓力升高，水溫達(dá)到50攝氏度左右就可以了。一般在車發(fā)動(dòng)后等半分鐘到一分鐘就能讓發(fā)動(dòng)機(jī)的機(jī)油達(dá)到各個(gè)部件表面。

Today's cars generally use electronic fuel injection nozzles. Different from the old carburetor models, the fuel supply system of EFI vehicles is controlled by ECU, which is not affected by air flow rate and temperature. The degree of fuel atomization is high, and the stable idle speed can be achieved in a short time after the engine is started. So it doesn't take too long to warm up the car. As long as the oil pressure rises and the water temperature reaches about 50 degrees Celsius. Generally, the engine oil can reach the surface of each component after waiting for half a minute to one minute after the car starts.

需要注意的是，除了需要時(shí)間讓機(jī)油覆蓋的零件之外，發(fā)動(dòng)機(jī)在持續(xù)工作之前還需要達(dá)到定的工作溫度。一般發(fā)動(dòng)機(jī)從環(huán)境溫度達(dá)到工作溫度需要7到8分鐘,但這個(gè)過(guò)程無(wú)需待在原地，只要不以高速行駛就可以。發(fā)動(dòng)機(jī)長(zhǎng)時(shí)間怠速會(huì)增加油耗和積炭，不利于。

It should be noted that in addition to the parts that need time to be covered with oil, the engine also needs to reach a fixed operating temperature before continuous operation. Generally, it takes 7 to 8 minutes for the engine to reach the operating temperature from the ambient temperature, but this process does not need to stay in place, as long as it does not drive at high speed. Idling the engine for a long time will increase fuel consumption and carbon deposition, which is not conducive to environmental protection.

綜上所述，自動(dòng)變速箱維修告訴我們熱車是比較重要的，所以在這里提示大家，做好相關(guān)的注意事項(xiàng)。

To sum up, the maintenance of automatic transmission tells us that hot car is more important, so here we remind you to do a good job of relevant precautions.