Before starting the engine, ensure the engine and wheels are disconnected from each other by pushing the clutch to the floor. In some cars, this is a requirement before the engine will start; in others, it is sufficient for the gearstick to be in the neutral position. It is a good safety precaution to push the clutch down regardless. This ensures the wheels will not turn when the engines starts.
Once the engine is running, it will turn at a slow speed without the need to add gas. When the gas pedal is pushed, the engine burns more fuel and turns at a faster rate. As long as the clutch stays down, the engine will not turn the wheels.
With a gear selected, lifting the clutch causes the engine to be connected to the wheels. The biting point
is the point at which the two clutch plates are just starting to touch. In the absence of anything holding the car back (such as the handbrake), the wheels would very slowly start to move at this point. Further lifting of the clutch will result in more power being transferred to the wheels, which will turn faster as a consequence.
With the clutch fully lifted, the engine and wheels turn together. Control over the speed of the car is now maintained using the gas and the brake. Prior to this point, the speed at which the wheels could turn was controlled mainly by the position of the clutch.
When applying pressure to the clutch with the engine running, be careful not to release the clutch too quickly. A sudden release of the clutch could cause a shock to the engine which will result in a stall: the engine suddenly stops running. This effect is most pronounced in first gear and becomes less likely as you increase speed and move into higher gears.
If you want to release the clutch while the car is stationary and the engine is still running, make sure you return the gearstick to the neutral position first. Doing so will completely disengage engine and wheels. If you fail to select neutral before releasing the clutch, either the wheels will turn or the engine will stall.
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