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How come "If you're driving slowly below 10mph and want to stop then press the clutch before the brake so that the car doesn't stall"? In other words, how does the clutch prevent stalling? Thank you!

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    Glen pretty much nails it. One "issue" I have with the statement in quotes (I assume you pulled it from the website) is, the original writer wrote "car" instead of "engine". Reading it the way it is, if you do not know better, you may think they are actually talking about the car, which the clutch has no ability to stall. They are actually meaning "engine" there and not "car". I can see how this might confuse the uninitiated. Apr 26, 2023 at 18:09
  • @Pᴀᴜʟsᴛᴇʀ2 I don't understand what you mean - in what way does stalling a car not mean exactly the same as stalling the engine?
    – MikeB
    Apr 28, 2023 at 12:17
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    @MikeB - You can stall the car without stalling the engine. If you completely stop the car, it has stalled, but the engine is still running. If you stall the engine, it stops running, but the vehicle itself can still be moving and not be stalled. Apr 28, 2023 at 12:20
  • @Pᴀᴜʟsᴛᴇʀ2 "If you completely stop the car, it has stalled" No, it has "come to a halt", that is all.
    – MikeB
    Apr 28, 2023 at 12:26
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    @MikeB - The act of "stalling" is to bring to a standstill. That's what is happening, but you can call it whatever you like. Those in the automotive realm would think of stalling as to kill the engine suddenly and without intention. Those who are not from the automotive realm (i.e. uninitiated) might not think that way. Apr 28, 2023 at 14:15

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The engine is connected to the drive wheels through the transmission. In order to continue to run (not stall) an engine needs to turn at a minimum speed (for instance 600 RPM). As a car slows down, the wheels will slow down, eventually to 0 RPM. At some point as you approach a stop, the wheels will turn so slowly that it would force the engine to turn slower than its minimum RPM required to keep running (this would stall the engine).

The clutch disengages the engine from the transmission and thus the drive wheels. This allows the engine to turn at a different RPM than the transmission (which could be potentially 0 RPM if you are stopped). This allows the engine to run with no load at its minimum RPM while the car is travelling very slowly or stopped.

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  • Thank you so much for your detailed explanations! I just have one more question: Once the clutch disengages the engine from the transmission and thus the drive wheels, the car is then traveling only with the help of the wheels - Is that a correct statement? Thank you once again!
    – Maurice
    Apr 26, 2023 at 20:00
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    @Maurice - If you want to be accurate, it's only traveling with inertia ... maybe that's what you mean? Depending on if the car is going downhill, gravity may be involved as well. Apr 26, 2023 at 20:33
  • Thank you for your answer! You are right, that was what I meant.
    – Maurice
    Apr 26, 2023 at 23:11
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    @Pᴀᴜʟsᴛᴇʀ2 additionally: when going downhill you may not want to put the clutch in, so you can use engine braking
    – user253751
    Apr 27, 2023 at 16:23

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