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Model specific boards => Golf mk7 => Topic started by: andyb_123 on 17 December 2017, 17:21

Title: Freewheel + start/stop on DSG Question
Post by: andyb_123 on 17 December 2017, 17:21
Somewhere in the manual it says that if you are in "eco" mode and you lift off in a certain speed range (30-80?), then the DSG will disengage and the engine will even stop.

I can get it to do the freewheeling thing (but only if I explicitly choose eco - it won't freewheel if I left it in eco and start a new journey from scratch without selecting again).

When we first got the car, I could swear on a downhill section it did freewheeling *and* turned the engine off, but it doesn't seem to want to do that anymore, even on a nice long downhill with nothing else around in front. When we come to a halt, the engine does switch off, so stop/start is working.

Is there some setting buried away somewhere? It probably doesn't really make much difference to consumption, but I'm more annoyed because I can't work it out  :smiley:
Title: Re: Freewheel + start/stop on DSG Question
Post by: maxie on 17 December 2017, 17:41
it will coast yes but you'll have to select eco each time you start a new trip.. it does say in the manual somewhere that some things will be deselected.. and tbh i dont think the engine will turn off when coasting as the brakes etc would stop working, it will turn off when you come to a complete stop if all conditions are ok within the car... :)
Title: Re: Freewheel + start/stop on DSG Question
Post by: Watts on 17 December 2017, 17:43
Not heard of that, the engine stopping bit, surely you'll lose servo assistance on the brakes and power steering? (With the engine off on start/stop on mine steering is nigh on impossible).
Title: Re: Freewheel + start/stop on DSG Question
Post by: itavaltalainen on 17 December 2017, 19:59
Facelift does turn the engine off.
Steering at speed doesn't actually take that much assistance, if it is required the battery can handle for a short while.
Same goes for braking, it probably has a modified brake servo that 'stores' more vacuum.
Title: Re: Freewheel + start/stop on DSG Question
Post by: andyb_123 on 18 December 2017, 13:12
The manual explicitly says the engine will switch off:

"Coasting
m/k/a995MKVehicles with DSG dual clutch gearbox: When the selector lever is in position D/S and neither the accelerator nor the brake pedal is depressed, the vehicle will roll (coast) with practically no energy being consumed.

The coasting with dynamic start-stop function means the engine is not just disengaged, but is also switched off."

I know about choosing ECO manually to get the coasting thing to work. I can confirm it does coast. But it doesn't seem to turn the engine off, yet when coming to a halt, the engine does stop. Presume that's what they call "dynamic start-stop function". I just wonder if there's a setting I've messed around with somewhere that I now can't find... My autistic side needs to know! (Probably would only save about 10p of fuel a year though...)

Here's the manual:
http://www.vw-manual.co.uk/browse?2&token=deniol2171.intern.nionex.netH1HtQWNKlgCGTcP&lang=en-GB&doc=5G0012720AE&link=RID (http://www.vw-manual.co.uk/browse?2&token=deniol2171.intern.nionex.netH1HtQWNKlgCGTcP&lang=en-GB&doc=5G0012720AE&link=RID)
Title: Re: Freewheel + start/stop on DSG Question
Post by: andyb_123 on 18 December 2017, 13:16
Sorry me again. Did a search for "coasting" in that PDF (much better than looking through the paper manual!) and it has this section:

"Switching on the start/stop system
The function is automatically activated every time the ignition is switched on. The instrument cluster display will show information about the current status.

Vehicles with DSG® dual clutch gearbox may be equipped with a start/stop system and a coasting with dynamic start-stop function. The coasting with dynamic start-stop function is deactivated and activated together with the start/stop system.

More information on start/stop system operation can be accessed in the Infotainment system using the m/b/v040MBm/b/v032MBm/b/v041MBm/b/v048MB button or function button and the Vehicle, Selection, Vehicle status function buttons. This information also applies to coasting."

Perhaps when I press the button which toggles the stop/start on and off there's a setting there. I did press that a few times before I knew what it was  :smiley:
 
Title: Re: Freewheel + start/stop on DSG Question
Post by: fredgroves on 18 December 2017, 13:50
I'd imagine the coasting engine off will only happen if the usual criteria for stop/start are met...

The main one which disables start/stop is if the heating/cooling system is active and actively heating or cooling (ie you have set an auto temperature and the cabin temperature is not currently at the temp demanded)

Wouldn't surprise me if you have it set to a relatively high setting (because its cold in the winter)

Other things also disable start stop functionality (fuel level is one, can't remember the others)

But in all of these conditions you should see a "A" with a line through it displayed on the dash.
Title: Re: Freewheel + start/stop on DSG Question
Post by: maxie on 18 December 2017, 13:53
Facelift does turn the engine off.
Steering at speed doesn't actually take that much assistance, if it is required the battery can handle for a short while.
Same goes for braking, it probably has a modified brake servo that 'stores' more vacuum.

when  mines coasting theres just a letter e instead of e3 etc, but i've never noticed the engine totally switching off. maybe it's a partial off like it just uses 2 cylinders etc?
Title: Re: Freewheel + start/stop on DSG Question
Post by: fredgroves on 18 December 2017, 13:56
No active cylinder tech on a VAG 2.0 TFSI engine... only the smaller engines have that.
Title: Re: Freewheel + start/stop on DSG Question
Post by: Sootchucker on 18 December 2017, 16:27
I've used this tech quite a few times on longer journeys on my DSG GTD, (admittedly not the FL version), and whilst the coasting works as advertised, the engine has never switched off (not sure I'd want it to).
Title: Re: Freewheel + start/stop on DSG Question
Post by: clarky92 on 18 December 2017, 18:11
I can confirm on my 7.5 GTI in ECO the engine will switch off and coast. I use this daily . A small e will appear on the AID instead of a gear selection.
Title: Re: Freewheel + start/stop on DSG Question
Post by: Sootchucker on 18 December 2017, 19:16
Are you sure it’s actually switching off, not just dropping down to idle revs (circa 700-800rpm), as that’s what mine does when I get the small “E” appearing in the MFD ?
Title: Re: Freewheel + start/stop on DSG Question
Post by: itavaltalainen on 18 December 2017, 19:23
It does actually switch off in facelift. I know for sure on the 1.5 TSI.
Title: Re: Freewheel + start/stop on DSG Question
Post by: maxie on 18 December 2017, 19:32
Are you sure it’s actually switching off, not just dropping down to idle revs (circa 700-800rpm), as that’s what mine does when I get the small “E” appearing in the MFD ?

same here :)
Title: Re: Freewheel + start/stop on DSG Question
Post by: JoeGTI on 18 December 2017, 20:09
The engine switches off? Wow. I thought the coasting thing was bad enough but that takes the biscuit. I detest that Eco mode nonsense and the start/stop thing - hence I've disabled it.
Title: Re: Freewheel + start/stop on DSG Question
Post by: wantmygti on 18 December 2017, 20:35
My CS will drop the revs to tick over and coast, but I don’t need to cycle though the driving programs each time I start the car.
Title: Re: Freewheel + start/stop on DSG Question
Post by: clarky92 on 18 December 2017, 21:26
The engine completely cuts out on my 7.5 GTI
Title: Re: Freewheel + start/stop on DSG Question
Post by: Don76 on 19 December 2017, 15:24
Sounds like only the petrol engines switch off. My facelift GTD DSG coasts at just over 500rpm but never switches off completely
Title: Re: Freewheel + start/stop on DSG Question
Post by: maxie on 19 December 2017, 15:28
The engine completely cuts out on my 7.5 GTI

yours must be set differently to mine, when driving in eco looks E3 etc when cruising/freewheeling it turns to E with an eco sign next to it (on the left)and the revs drop to 800rpm but still it is not turned off. the only time it does turn off is at a full stop.
Title: Re: Freewheel + start/stop on DSG Question
Post by: hog_hedge on 19 December 2017, 22:15
My 7.5 completely shuts off too but only on long downhill stretches, I thought the car had given up the ghost the first time it happened.
Title: Re: Freewheel + start/stop on DSG Question
Post by: maxie on 21 December 2017, 10:39
Sounds like only the petrol engines switch off. My facelift GTD DSG coasts at just over 500rpm but never switches off completely

mines a gti pp and it revs at around 800 when coasting, not sure whats what..lol :)
Title: Re: Freewheel + start/stop on DSG Question
Post by: Mark V GTD on 21 December 2017, 10:45
How does the PAS steering work with engine off?

My 2016 mk.7 switches of the engine just before actually coming to a halt (if I have forgotten to switch off start/stop) and you can immediately feel the steering go very heavy.
Title: Re: Freewheel + start/stop on DSG Question
Post by: Wide on 21 December 2017, 13:03
How does the PAS steering work with engine off?

My 2016 mk.7 switches of the engine just before actually coming to a halt (if I have forgotten to switch off start/stop) and you can immediately feel the steering go very heavy.

It is dangerous, i almost have "crashed" in to my garage several times when the engine switch of and i can´t steer.. :angry:
Title: Re: Freewheel + start/stop on DSG Question
Post by: Jim_mk7.5 on 22 December 2017, 11:05
On Eco mode I get mine to coast in 'E' but never had the engine switch off while coasting....