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From the Porsche Technik Book

Auto Start Stop function

The Macan models are equipped with an enhanced Auto Start Stop function. The enhanced Auto Start Stop function switches off the combustion engine under defined conditions at speeds of less than 1 mph (2 km/h) and therefore exploits additional fuel- saving potential. The DME control unit that controls the Auto Start Stop function has been optimized so that the engine can be switched off automatically in as many cases as possible to minimize fuel consumption for the driver in day-to-day use.
The Auto Start Stop function can be activated and deactivated by way of a button in the center console (1). The function is available as soon as the coolant temperature, engine oil temperature and transmission fluid temperature have exceeded a certain temperature, the air conditioning system has reached its setpoint temperature and all other operating conditions in accordance with the Owner’s Manual are met. If the vehicle is stopped by brake operation and the brake pedal is held down, the Auto Start Stop function switches off the engine at a speed of less than 1 mph (2 km/h). The driver is informed of this by the green Auto Start Stop symbol (bottom figure – 2) in the instrument cluster. The tachometer falls to zero. The selector lever can remain in position D or M. The engine remains stopped even if the lever is shifted to P or N. If the engine cannot be switched off automatically, the driver is informed about this by a yellow Auto Start Stop symbol (bottom figure – 3) in the instrument cluster when the vehicle is stationary.
The engine is not switched off or restarted again in this case, if for example:
• “Sport” mode is activated
• Vehicle electrical system voltage is too low
• Maneuvering or parking is detected, i.e. reverse gear is engaged or the steering
wheel is turned by a large angle
• Climate control/heating with residual heat function cannot guarantee that the set temperature can be maintained without running the engine
• Also at very low and very high outside temperatures
• The air suspension is adapting the vehicle level
If the driver’s door is opened after an automatic stop when selector-lever position D or N is engaged, an automatic engine start is executed to remind the driver that the Auto Start Stop function is still active. In selector-lever position D, the parking brake is additionally engaged. The brake warning light appears on the instrument cluster and the indicator light on the parking brake switch lights up. If the vehicle is left after an automatic engine stop when selector-lever position P is engaged, no automatic engine start is executed. Auto Start Stop mode is resumed if the driver closes the driver’s door and presses the brake within 30 seconds of leaving the vehicle. If one of these requirements is not met, the engine has to be started manually. The message “Please start engine manually” will appear on the multi-function display in the instrument panel.

Coasting function
The Macan models feature the coasting function. Coasting refers to operating the vehicle with the engine disengaged, for example on slight downhill gradients; the engine is operated at idle speed so that the function of the auxiliary systems (alternator, air conditioning compressor, coolant pump, etc.) is maintained. During coasting, the kinetic and potential energy of the vehicle is directly used to overcome running resistance forces.
Although no fuel is used during deceleration with deceleration fuel cutoff, the vehicle is decelerated significantly more. If no deceleration is desired, additional fuel must be used to cover the lost distance. After the driver gently presses the accelerator, the engine revs up smoothly and immediately with early upshifts; after the driver gently releases the accelerator, the engine intermittently coasts with the clutches disengaged and at idle speed until the brake is pressed or the accelerator is pressed again. If the driver wishes to coast for a certain distance, for example when approaching a built-up area, the engine is automatically disengaged and kept at idle speed. The vehicle can therefore coast for a longer distance than in engaged state, leading to lower fuel consumption.
If the driver indicates a wish to decelerate by pressing the brake, the engine is immediately re-engaged in order to use the engine’s trailing throttle fuel cutoff; the fuel supply is interrupted during this process and the engine braking effect additionally shortens the vehicle’s stopping distance. Coasting can alternatively be intentionally activated by manually shifting up above the current maximum possible gear. The savings that can be achieved depend on the driving style and conditions of use. The efficiency of the function depends on an anticipatory and relaxed driving style; after a short familiarization time, the driver will have become accustomed to the longer coasting distance of his/her vehi- cle. The disengagement and engagement operations are imperceptible to the driver. The tachometer dropping to idle speed is the only indication to the driver that he is in coast- ing mode. The Auto Start Stop button switches the Auto Start Stop function on and off and activates and deactivates coasting mode. When the system is switched off, the indicator light in the button lights up “red”.
The preconditions for coasting mode include the following:
• Driving with selector lever in position D
• Coasting mode is activated (indicator light in the button is off)
• Sport or Sport Plus mode deactivated
• PSM active
• Cruise control mode not active
• Engine, transmission and battery have reached operating temperature
• Relaxed/economic driving style
• Slight uphill gradients (up to approximately 10%) or slight downhill gradient • Remove foot slowly from accelerator pedal
Vehicle electrical system recuperation
When the accelerator pedal is released quickly, the DME control unit detects that the driver does not want the coasting function. Deceleration fuel cutoff is initiated in conjunction with vehicle electrical system recuperation in these cases. To this end, the genera- tor power is increased in a targeted manner by the generator regulator during braking and the recuperated energy is fed into the starter battery. The increased generator power acts with a higher braking torque on the crankshaft of the combustion engine via the belt drive. This leads to vehicle deceleration, boosting the conventional brake system. The voltage is lowered again during acceleration and the available energy can be fed into the vehicle electrical system in order to supply the electrical consumers. This reduces the load on the combustion engine, and the full drive power can be made avail- able for propulsion. An intelligent algorithm in the energy management system evaluates various input variables of the components involved, thereby allowing active coordination of every recuperation operation based on the battery charge condition and driver request.
 

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Mark, people should note, however, that in many states coasting is illegal when driving downhill. For example,

"If a motor vehicle is traveling on a downgrade, the driver of the motor vehicle may not coast with the gears or transmission in neutral."

Not sure if anyone ever got a ticket for it but you can get one.
 

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Mark, people should note, however, that in many states coasting is illegal when driving downhill. For example,

"If a motor vehicle is traveling on a downgrade, the driver of the motor vehicle may not coast with the gears or transmission in neutral."

Not sure if anyone ever got a ticket for it but you can get one.
I really doubt that would apply to automatic coasting managed by the car's computer. How would they prove you were coasting anyway? The gear selector stays in D the whole time.
 

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I really doubt that would apply to automatic coasting managed by the car's computer. How would they prove you were coasting anyway? The gear selector stays in D the whole time.
Many states have this law and not just mountainous states. I guess the reasoning is if the car is not in gear, then you can't react fast enough. Turns lots of people have got tickets for this.

Ticket for coasting? - GirlsAskGuys
got a ticket for "coasting" - CamaroZ28.Com Message Board
In CA my husband got a speeding ticket someone told him to claim "Coasting" but isnt that worse?
Has anyone ever gotten a ticket for EOC? - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
The Way It Oughta Be: Coasting Ticket | kplr11.com

Maybe the law needs to be updated or not. Sometimes technology gets ahead of the laws. In any case, its illegal and I suspect a cop can and will give you a ticket. Whether or not you get convicted is another story.
 

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Discussion Starter #5
Technically the gears nor transmission are in neutral, so no ticket would apply. The vehicle is in Drive at all times and the feature is intended to reduce emissions. I think any authority that tried to prosecute that would have a hard row to hoe.
 

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Technically the gears nor transmission are in neutral, so no ticket would apply. The vehicle is in Drive at all times and the feature is intended to reduce emissions. I think any authority that tried to prosecute that would have a hard row to hoe.

"Coasting refers to operating the vehicle with the engine disengaged .. engine intermittently coasts with the clutches disengaged"

Sure sounds like the transmission is not linked to the engine. Otherwise, the transmission would be engine braking. Clutches disengaged is coasting.

"the driver of the motor vehicle may not coast with the gears or transmission in neutral."

Sure sounds the same to me.

§ 40-6-246 - Coasting :: 2010 Georgia Code :: US Codes and Statutes :: US Law :: Justia

The driver of any motor vehicle when traveling upon a down grade shall not coast with the gears or transmission of such vehicle in neutral.


New York Article 33 | NYS Vehicle Traffic Law | Miscellaneous Rules.

The driver of any motor vehicle when traveling upon a down grade shall not coast with the gears of such vehicle in neutral, nor with the clutch disengaged.

CA 21710. The driver of a motor vehicle when traveling on down grade upon any highway shall not coast with the gears of such vehicle in neutral. Discussion on Teslas and coasting.

We can rationalize things but if the cop wants, he can write the ticket. Getting convicted might be something else. Coasting is coasting.
 

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Again @grim, how is any cop going to a) detect this and b) prove it in court. It's just one of those dumb laws that are left behind from earlier times that are no longer enforced, like the one about a pickle not being a pickle unless it bounces.

California has a no-coasting law I believe, and I will not be letting it stop me using the coast feature if I so wish.

Also, don't forget that vehicles have to go through various compliance processes and something like this would already have been vetted and determined to be acceptable. If something is not in compliance, it would be disabled, like the advanced dynamic LED headlights on some cars.
 

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Hi all
I have noticed that once the auto start-stop has turned the engine off (after coming to a stop) the car often starts up again on its own without me doing anything. Can anyone tell me if this is a timing thing or am I causing this to happen? Thanks....
 

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Again @grim, how is any cop going to a) detect this and b) prove it in court.
Ticket for coasting? - GirlsAskGuys

CA coasting ticket.

In California, is it true that c.v.c. 21710 carries zero points towards my driving record? - Avvo.com

https://answers.yahoo.com/question/index?qid=20110213161428AAtLyoJ

Shocked to find California Highway Patrol officers involved in corruption. - One Citizen Speaking (handing out coasting tickets)

California Motor Vehicle Code 21710 - Coasting Downhill Prohibited reasons for this law

Also, don't forget that vehicles have to go through various compliance processes and something like this would already have been vetted and determined to be acceptable. If something is not in compliance, it would be disabled, like the advanced dynamic LED headlights on some cars.
Not buying that. I do believe that the laws haven't caught up with technology and maybe need to change. But that won't stop a cop from giving you a ticket if he wants to. Companies sell products all the time that say "For off road use only" yet consumers buy them and use then on public roads. Then get ticketed.

I don't really know if PDK coasting falls under this law but I read nothing to indicate it does not. I also see nothing preventing a cop from issuing the ticket. They don't make the laws. Then you have the aggravation of dealing with it. Does anyone care?

Nobody cares until they get a ticket. Almost everyday I see people flying through construction zones and speed camera zones clearly showing their speeds and cameras in use. Then a ticket appears in the mail and they get all upset. Duh.
 

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Discussion Starter #10
The only way I imagine anyone possibly getting a "coasting" ticket would be if they were involved in an accident and it was determined that the cause (or even a contributing factor) was coasting - how they would discover or prove that I have no idea. I believe the original intent of this law was because people were overheating their brakes and causing accidents. The Macan, however, stops coasting as soon as you apply any brake at all and begin engine braking.
 

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Hi all
I have noticed that once the auto start-stop has turned the engine off (after coming to a stop) the car often starts up again on its own without me doing anything. Can anyone tell me if this is a timing thing or am I causing this to happen? Thanks....
I think the primary culprits are (a) drain on battery thus asking for charge, (b) climate control not being able to hold the requested value, and (c) a small change in steering angle can also restart the engine.
 

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The only way I imagine anyone possibly getting a "coasting" ticket would be if they were involved in an accident and it was determined that the cause (or even a contributing factor) was coasting - how they would discover or prove that I have no idea. I believe the original intent of this law was because people were overheating their brakes and causing accidents. The Macan, however, stops coasting as soon as you apply any brake at all and begin engine braking.
The intent of the law was associated with mountain states and drivers coasting down the hills. Without engine braking, yes brakes failed. But its more than that, its the time to reengage the engine.

I provided links to real tickets. Tickets happen. Whether or not there are convictions, don't know but there is aggravation. CA has been using the law to give some slack to speeders (or so it seems).

This might be a case of the laws not catching up with technology. But the laws exist, are real, and people get tickets based upon them.
 

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Gotta love the law. So in NY it's illegal to coast but legal for women to walk around in Times Square without a top (see today's NY Times). Seems that the latter is more likely to result in accidents, i.e., distracted drivers and all. I'll alert the Mayor's and Governor's office, each is seeking a way to curb it. Regarding this law, although common sense does not always apply, in my opinion such a ticket could never stick if the shift lever is in D and not N. Also, as others have said, there is no way for a police officer to know whether a driver was coasting unless the driver states they were doing so, and those who admitted it most likely had no idea it was illegal. When asked a Macan driver can correctly state that the shift lever was in D.
 

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I have a six speed manual transmission. That means on my way to top gear my gears and my gear shift are in neutral or disconnected 5 times. Does that make me a coaster ? And if I'm going east, does that make me an east coaster ?
 

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Discussion Starter #15
My intention with this thread was to provide people with as much knowledge as possible about the Auto Start-Stop system. Seems to have gotten off track a bit.
 

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...the air conditioning system has reached its setpoint temperature and all other operating conditions in accordance with the Owner’s Manual are met....
• Climate control/heating with residual heat function cannot guarantee that the set temperature can be maintained without running the engine
Well I don't need to worry about Auto Start stop, as the weather during the summer hear is usually 110 degrees! so will assume its auto ON mode ... we have two seasons here, one covering most of the year when it is very hot, and then the other during winter when it is just hot :)
 

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Hi all
I have noticed that once the auto start-stop has turned the engine off (after coming to a stop) the car often starts up again on its own without me doing anything. Can anyone tell me if this is a timing thing or am I causing this to happen? Thanks....
The A/C system likely needs to recharge and bring the cabin up to the assigned temp. Turn the A/C off, and the engine will not restart as much or at all unless you wish to drive on.
 

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@MarkInMd... Thanks for your original post. I printed it out and will keep it handy for when I take delivery next month!

:)
 

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@MarkInMd, it was greatly appreciated. Probably so thorough, nobody had anything useful to add. So we digressed...

Auto Start/Stop rarely functions for me. I have a short drive to work and hot summer or cold winter, it rarely does the start/stop thing. I use auto start/stop when highway and byway driving, because it turns off the fuel when you let your foot off the gas and does improve mileage. However, it does not work when you are in cruise control mode. Odd, eh ?
 
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