How to drive an automatic car

Posted by Faisal Naser On Wednesday, January 30, 2013 0 comments

Driving an automatic car, a priori, should pose few headaches, as these vehicles are designed for comfortable handling without addressing concerns over traffic themselves. However, in our environment, where we tend to form with manual shift car, sometimes there are doubts about how to drive a car with automatic transmission.
Mercedes-Benz GLK 250 BlueTEC 4MATIC

Understanding the automatic
If engine braking when we explained graphically representing the marches, today we refer to automatic transmissions very abbreviated form. The basically have three types:
Automatic transmission engine
Conventional hydraulic shift, also called manually driven: the form of a manual gearbox which is coupled a hydraulically actuated electronically controlled for gear selection. As in the background is a manual change no problem in giving it a way in which the driver selects the gears at will, either on the lever or paddles on the steering wheel arranged with upshift (+) and downward ( -). In the more advanced models of these transmissions, with names like DSG, EDC, Powershift or TCT, marches ahead to prepare the way for the next relationship is almost imperceptible.
Automatic switch with epicyclic trains, which employ a three pinion planetary pinions and connected by a common plate in a ring gear by its inside. 100% is the automatic change over has been used despite their technical complexity and allows several relationships according to the pinions which engage at all times without interrupting the entry movement of the motor, may be employed where a torque converter.
Change continuously variable, nicknamed CVT Multidrive S, Hypertronic, Multitronic, Autotronic, Extroid or Xtronic, is both the simplest from a conceptual point of view and the most evolved in terms of energy efficiency. Assumes mount two variable diameter pulleys and a flexible metallic chain link between the two, which is transmitting the movement. The management is done with an electronic control and allows for an infinite number of gear ratios, as there is no fixed positions but everything is quite variable. This change is well understood if it is running:

Automatic Car Controls
From all this we get a first idea, and each manufacturer is riding his car as he wants, so consulting the instruction manual is more necessary than ever to know how the manufacturer has designed the automatic car specifically what behavior expected of us as drivers and how much leaves the car to handle. From there, we met some generalities that can apply to most automatic cars.
automatic car control
The first has to do with the pedal, this is the pedal assembly. As in automatic cars eliminates the clutch pedal, the first practical recommendation on handling a car with automatic transmission has to do with ergonomics and summarized in a single warning: beware the left foot.

Yes, yes. Sounds like a joke, but it is not. By habit, who drive vehicles with manual transmission that we have very integrated that with the left foot must tread to the bottom, and when we removed the clutch pedal not know what to do. Well, put your foot on the running board (which is its home position even in cars equipped with clutch pedal) and if necessary we fix shoelace to the driver's door. Because to do so, and if the habit betrays us, we can make a spectacular dunk brakes in the wrong time.

The second finding is related to the possibilities of automatic gearshift beyond the cam gear selection, either on a lever, button or whatever the manufacturer has provisions that let the car handle. For power, we can find plenty of positions: P, R, N, D, 2, 1 (or L) and even D3, D4, S, DS and more residual OD.

The basic positions are: P, "parking", to immobilize the vehicle when it is stopped, R, which is "pulling" or "reverse", N, equivalent to "neutral" or "neutral" and D which is "driving" the English "Drive".

Other positions are those that are numbered, to select specific regime explicitly depending on driving circumstances, and sufficiently close to a manual. This is the case of 2, D4 or L, which equals 1, the lower gear. Some models have the position S or DS, emphasizing acceleration in low gears, and we could even find the OD position, which allows one jerk in higher gears at a timely demand higher than normal. Alternatively, buttons can be locked to prevent or allow the lever to move from one position to another.

Management depending on driving conditions

The automatic transmission is designed to avoid having to think about it. This means that the natural position is D drive (unless you want to go into reverse, of course). With the vehicle stopped, the brake pedal is depressed, the engine is started, the position D is selected and carefully removed the brake pedal as the car starts moving. The dynamic response of the vehicle in gear reminiscent of a manual transmission car.

From there, depending on the circumstances may be interested select a lower gear than normal to, to give classic example, down a mountain pass. If we kept the D, to accelerate the engine box would select a higher ratio. This is avoided by imposing the gear lever and selecting, for example, 2. In addition, we have the example of hybrid cars, where D is used always, except when the car features a special mode of retention, and thus force the gasoline engine turns without consuming fuel, only to produce drag.

In fact, there are two types of sequential changes: those that adhere to the request of the driver and, if the ruling permitting electronic low or high speeds, the gear selected, and those in which the driver selects the highest gear possible. That is, when we see a lever D4 progress, for example, does not indicate that by selecting the car all the time to stay in 4th, but works in gear but not passing 4th, retaining a bit. This prevents an excessive number of positions in the selector lever.

An additional note: in some machines, the virtual absence of engine braking causes the driver accustomed to manual changes have the perception that the car was going more. It's a matter of using the brake pedal to be selected for shorter relationships ... or impose manually. In CVT changes with gear selector to select one of these changes reduce the operating range of the combinations that we can help more then.

And in detention for reasons specific traffic or signaling? Should we remove the fly? Here is some controversy depending on who inquire. Some talk of move to N to prevent D causes parasitic drag and fuel consumption and some people choose N indicates that every moment is equal to unnecessary wear on the mechanism. Who were we? I'll stick with the first option unless detention is very short.

The position P, meanwhile, is designed to hold the vehicle when it is stopped, depending on the model and the car may not start if not in that position, as the other possible selections wheel motion transmitted to the motor . For the same reason, it may be impossible to pull the lever P if no steps on the brake or it may be that we can not remove the key if the car is not in P.

In specific demands acceleration, S or DS modes impose a more sporty stretching the use of gears and even accelerates the transition time between gears. In these modes of transmission, the gears might also retain more. Releasing the throttle lever can be returned to another position.

Under conditions of low grip, the marches should be long on the flat and uphill to prevent loss of grip and falls short in the car to prevent the accelerated increase of the motor gears. In these cases we will choose gear selection according to these premises and avoid selecting sport mode. If we have the so-called "winter mode", we will use it, as this will give priority to the most appropriate relationships depending on the time of driving.

As card of automatic transmissions, rather than tutorial, I think this article may help. The rest, better consult the manual for each car.


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