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Discussion Starter #1
I don't like the start/stop function but I do appreciate the coasting feature.
The coasting function is not possible when start/stop is deactivated.
So instead can I just put the car in neutral when I want to coast? I have a PDK


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Putting it in neutral is not similar to coasting as you'll lose momentum overtime... that's what I read somewhere. For me, the function will stay off for stop/start and coasting. I'm not interested to try this feature.
 

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I don't like the start/stop function but I do appreciate the coasting feature.
The coasting function is not possible when start/stop is deactivated.
So instead can I just put the car in neutral when I want to coast? I have a PDK


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So much easier just to activate start stop function (and therefore coasting mode) when driving and deactivate when coming to a halt. It's just one push of a button on the centre console....
 

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I wasn't sure about the start/stop and the coasting functions. However, yesterday I went on a 140 mile trip and I used them both. I took two-lane roads to my destination (with a lot of driving through small towns) and I came back on the interstate. I averaged 33 miles to the gallon. This is a new car that isn't broken in yet and I got 33 miles to the gallon! I was impressed.

If I am out to have fun I will put my car in "sport" and not worry about fuel mileage but if I am just driving around I will see what kind of mileage I can get. :cheers:
 

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I got a whole 38 MPG on a 50ish MPH highway trip before thanks to nice weather, the coasting feature, and being stuck behind a train of cars following grandma. I reset the MPG meter at a gas station after the car was warmed up.
 

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Discussion Starter #6
So much easier just to activate start stop function (and therefore coasting mode) when driving and deactivate when coming to a halt. It's just one push of a button on the centre console....
That's not the question I asked.
Let me repeat.."is the coasting function similar to putting it into neutral"


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Discussion Starter #7
Putting it in neutral is not similar to coasting as you'll lose momentum overtime... that's what I read somewhere. For me, the function will stay off for stop/start and coasting. I'm not interested to try this feature.
Thanks Hassaan for the technical answer.


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According to Porsche, coasting is much like putting the car in neutral. From the Porsche website we read -

"Coasting

The coasting function available with Porsche Doppelkupplung (PDK) enables you to save even more fuel where the situation allows. The engine is decoupled from the transmission to prevent deceleration caused by engine braking. In this way, optimum use is made of the vehicle’s momentum, allowing it to coast for longer distances.
For example, you may want to slow down 62 mph to 50 mph in anticipation of the change of speed limit ahead. As you ease off the accelerator pedal, PDK deselects the current gear automatically and you begin to coast in neutral until you have reached your desired speed. As soon as you operate the accelerator or brake pedal, PDK re-engages the appropriate gear within fractions of a second. The process is smooth and seamless thanks to the extremely fast clutch.
Another way to reduce fuel consumption is to utilize the coasting function on downhill gradients that are gentle enough for you to maintain a constant speed. Efficient on long journeys, such as on the highway, PDK remains ready to respond as swiftly and precisely as you would expect.
In short, driving in coasting mode makes a real impact on fuel consumption without any need for compromise on comfort or sporty performance."
 

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In my most states, it is illegal to have your car in motion without the drivetrain engaged, i.e. holding the clutch in or putting the car in neutral. Was actually stopped for speeding down a large hill in PA one time and the officer asked if I had put the truck in neutral since he saw my speed increase. He then told me about how that is illegal and I could be ticketed for it. Not sure how the law would apply to the Porsche "Coasting" feature as it does allow for instant gear engagement.
 

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Discussion Starter #10
In my most states, it is illegal to have your car in motion without the drivetrain engaged, i.e. holding the clutch in or putting the car in neutral. Was actually stopped for speeding down a large hill in PA one time and the officer asked if I had put the truck in neutral since he saw my speed increase. He then told me about how that is illegal and I could be ticketed for it. Not sure how the law would apply to the Porsche "Coasting" feature as it does allow for instant gear engagement.
Such a peculiar law. How can one prove that and thus enforce it.
Is it a real law or did the cop thumbsuck?


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You can look it up online for your state to see if they have such a law. My stop was made by observation from the officer on a large highway down hill.
 

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Guys, For long road trips, which is actually more fuel efficient, coasting or using cruise control?


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According to Porsche, coasting is much like putting the car in neutral. From the Porsche website we read -

"Coasting

The coasting function available with Porsche Doppelkupplung (PDK) enables you to save even more fuel where the situation allows. The engine is decoupled from the transmission to prevent deceleration caused by engine braking. In this way, optimum use is made of the vehicle’s momentum, allowing it to coast for longer distances.
For example, you may want to slow down 62 mph to 50 mph in anticipation of the change of speed limit ahead. As you ease off the accelerator pedal, PDK deselects the current gear automatically and you begin to coast in neutral until you have reached your desired speed. As soon as you operate the accelerator or brake pedal, PDK re-engages the appropriate gear within fractions of a second. The process is smooth and seamless thanks to the extremely fast clutch.
Another way to reduce fuel consumption is to utilize the coasting function on downhill gradients that are gentle enough for you to maintain a constant speed. Efficient on long journeys, such as on the highway, PDK remains ready to respond as swiftly and precisely as you would expect.
In short, driving in coasting mode makes a real impact on fuel consumption without any need for compromise on comfort or sporty performance."
This means Coasting is another term for neutral except that you don't need to push the gear from D to N.

What a waste of technology!
 

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Discussion Starter #14
This means Coasting is another term for neutral except that you don't need to push the gear from D to N.

What a waste of technology!
Hassaan. Now you go and contradict your first statement that neutral is different from coasting

Now I'm thoroughly confused


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Hassaan. Now you go and contradict your first statement that neutral is different from coasting

Now I'm thoroughly confused
My dear buddy from South Paradise, let me clarify the following:
1) I don't care about fuel consumption unless I have a red light on the fuel gauge which rarely happens, about once every 2 to 3 years.
2) therefore, I care less for coasting and stop/start.
3) I previously understood that coasting keeps the car going by making use of the car momentum yet engaging the gear occasionally to maintain momentum... Obviously I was wrong as per the comment I quoted in my last post by Spencer.
4) if my comments confused you and jeopardized our Porsche fellowship, I donate a camel to feed your angry lions :kiss:

:burnout:
 
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Unlike physically moving your transmission from "Drive" to "Neutral" the coasting function is seamless. You don't have to think about it.

When I am mindlessly droning along the Interstate I will use the coasting function. The Interstate is boring anyway. I might as well save some fuel while I am driving it.
 

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Discussion Starter #17
My dear buddy from South Paradise, let me clarify the following:
1) I don't care about fuel consumption unless I have a red light on the fuel gauge which rarely happens, about once every 2 to 3 years.
2) therefore, I care less for coasting and stop/start.
3) I previously understood that coasting keeps the car going by making use of the car momentum yet engaging the gear occasionally to maintain momentum... Obviously I was wrong as per the comment I quoted in my last post by Spencer.
4) if my comments confused you and jeopardized our Porsche fellowship, I donate a camel to feed your angry lions :kiss:

:burnout:
Haha. No offence taken. The fellowship is intact.

The lions are well fed here. No camels required.
Here is a pic of my nephew at the lion park.
ImageUploadedByTapatalk1431886441.500415.jpg



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If traveling in the mountains or the red reserve light is on, I might use the auto stop. Otherwise I like engine braking, and I hate engine auto stop. The only part of it I like is the auto start if I stall it, and I get that with it turned off.
 

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I'm not crazy about the feel of the coasting function. Feels like hesitation when I un coast because the engine has to come up from idle. I wonder about extra wear on the clutches and actuators, too. It is cool for saving fuel, but I'm often on ACC, so don't get to use it. And also always in Sport mode. But I were low on fuel...
 

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Didn't see this mentioned, but on a pdk with the paddles, pulling back both paddles simultaneously will put the car in neutral. I do this sometimes to coast and at traffic lights, so my foot isn't resting on the brake.
 
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