Having recently acquired my Karoq, I’ve discovered what J believe is the DSG coasting feature. Something my 2013 Touran DSG did not have. The comments I read on the VW forum when coasting became available on the Golf (7.5?) were mostly unfavourable and also mentioned 2 cylinder mode, again often unfavourably. Mg understanding is that coasting will occur when lifting off from a light throttle setting, the gear display changes to a single letter without the number, I.e D or E or M or S, the engine does not switch off but revs drop to about 800 rpm. Touching either pedal re-engages the gearbox seamlessly. On undulating A and M roads it’s possible to coast for a mile or more without losing speed or to coast up to slower moving traffic. I think it does require concentration on reading the road and anticipation but it seems to me that it must save fuel. Especially as disengaging cruise control, even when set to 70 mph, will drop into coast mode, even on inclines. I don’t have adaptive cruise has anyone discovered if that uses coasting? How do others feel about the viasting feature?

Your understanding is spot on. Like you, I wasn't aware of the coasting feature before buying my present  Karoq. My previous Karoq DSG did not have this function.

I suppose it must save a little fuel - you still use the same amount uphill but a little less downhill, at the expense of a small increase in use of the brake disc pad wear due to having no engine braking.

Occasionally I think I am travelling too fast towards slow moving traffic. On reflection I can give it grudging approval if it uses a little less fossil fuel. I do not have adaptive cruise control so cannot comment on that. 

@OldKaroq  Just a small point over 'Coasting ' with your 1.5 TSI ACT DSG in comparison to @thamestrader,s 2.0TSI DSG is the Active Cylinder technology so as well as 'Coasting' you have gong down to 2 cylinders when no load on the engine and under the correct conditions.

Then there are 1.0 TSI,s or 2.0 TDI,s.  All can have coasting and it does the same thing but not all ages of the different drive trains are selecting it or operating the same, some need to be in certain modes.

Certainly improves consumption. If you have your display set to show mpg it'll read around 90 to 100 when in coast mode

I am easily confused, and this has me puzzed. Am I right in thinking that on a DSG car, in coasting mode the engine is still running? If so it is using fuel. If however the car were in gear, taking your foot off the throttle would cut the fuel supply to the engine, therefore using no fuel at all. So if you are on a motorway doing 70mph and there is a jam ahead, in the first case you would be using fuel to idle the engine, then applying brakes to stop the car. If however it stayed in gear you would use no fuel, then apply the brakes from a lower speed resulting in less brake wear. Doesn't really add up to me. 

10 minutes ago, sussamb said:

Certainly improves consumption. If you have your display set to show mpg it'll read around 90 to 100 when in coast mode

My 1.5 TSI ACT DSG reads no consumption in coasting mode. With light throttle control it uses ACT a lot of the time too.

I really like it.

1 hour ago, Routemaster1461 said:

I am easily confused, and this has me puzzed. Am I right in thinking that on a DSG car, in coasting mode the engine is still running? If so it is using fuel. If however the car were in gear, taking your foot off the throttle would cut the fuel supply to the engine, therefore using no fuel at all. So if you are on a motorway doing 70mph and there is a jam ahead, in the first case you would be using fuel to idle the engine, then applying brakes to stop the car. If however it stayed in gear you would use no fuel, then apply the brakes from a lower speed resulting in less brake wear. Doesn't really add up to me. 

 

You're right, it does use fuel in coasting to keep the engine running but tickover uses miniscule amounts of fuel so I presume on balance someone has decided that coasting does saves fuel.

 

I have to say I don't really like it - it does feel at times like the car is running away with itself.  We used to have a diesel Tiguan and it was selectable on that but I never used it.   I had a loan ID.3 for a few days and I loved the one-pedal driving - rarely had to touch the brakes.   Against that, if you don't use the brakes they just go rusty!   We used to have ex-police defensive driver trainers at work and they were very much (in manual cars) "gears to go, brakes to slow" drivers - they would pull you up if you used engine braking to slow the car.

 

Wonder how smart alternators cope with this - they charge more when lifting off.   Tiguan had that system and I assume Karoq does (most "modern" cars do).  Maybe that's why the engine stays at idle rather than shutting off?

A couple of points.

 

On the road, day to day driving, comparing the classic lift off closed throttle situation where there is engine braking and the car slows down coasting doesn't require opening the throttle to get back up to speed.  In this sense less fuel is burnt.

 

Secondly on one particular downhill urban road I use the car goes into coasting mode.  However because of the steepness of the hill it accelerates and then the gearbox reengages to slow it down.  I don't have ACC.

 

The system is obviously more sophisticated than we give it credit. 

 

tom

33 minutes ago, Sanqhar said:

 

On the road, day to day driving, comparing the classic lift off closed throttle situation where there is engine braking and the car slows down coasting doesn't require opening the throttle to get back up to speed.  In this sense less fuel is burnt.

 

 

I don't follow that - why would you lift off if you didn't need to slow?  Sure, you're sub-conciously constantly adjusting how much you're pressing the gas pedal, but not coming right off it unless you want to slow down.

 

33 minutes ago, Sanqhar said:

Secondly on one particular downhill urban road I use the car goes into coasting mode.  However because of the steepness of the hill it accelerates and then the gearbox reengages to slow it down.  I don't have ACC.

 

 

Is that with normal cruise on?  There's a long steep dual carriageway hill near our house and our Karoq does not attempt to control itself unless cruise (also don't have ACC) is on.    Have to be careful because the dual carriageway ends at the botton of the hill so the speed limit changes to 60 and it's a favouite spot for a camera van to hang out!   Even with cruise on it's not that good at holding the speed on the hill - our old diesel Tiguan was spot-on.

Edited 19 June, 20241 yr by Rory

You do not have a self drive car. (yet)  You still drive it, touch the accelerator or brake if needed or shifter or paddles.

 

As it is Cruise Control can be a fuel waster and keep the power on and using fuel into corners where you might lift off the accelerator and carry speed in and around.

Like Coasting decades back before 'coasting'  was a thing, or even a DSG was.  Or ACC, or GPS controlling power, cylinders, engine off, cylinder on demand etc. 

2 hours ago, Sanqhar said:

Secondly on one particular downhill urban road I use the car goes into coasting mode.  However because of the steepness of the hill it accelerates and then the gearbox reengages to slow it down.  I don't have ACC.

 

The system is obviously more sophisticated than we give it credit. 

 

There are clearly variations between cars, possibly related to engine and DSG version, my DSG does not re-engage if the speed increases, luckily the max speed warning was set to 75 and it alerted me.

 

I think battery level may and engine load may also be a factor. This morning first thing, with a fully charged battery and cool conditions coasting was active on a short journey, but mid morning when A/C was on and battery level may have dropped due to stop[/start usage, coasting was inactive.

 

1 hour ago, Ootohere said:

As it is Cruise Control can be a fuel waster and keep the power on and using fuel into corners where you might lift off the accelerator and carry speed in and around.

Like Coasting decades back before 'coasting'  was a thing, or even a DSG was.  Or ACC, or GPS controlling power, cylinders, engine off, cylinder on demand etc. 

Agreed I found on my 260 trip yesterday with CC set to 70  that when coasting revs dropped to idle (around 800 rpm) whereas without coasting revs stayed at around 1800 rpm, more fuel must be used at 1800 than 800 rpm.

 

Although the dashboard mpg figure can show "---" i suspect this means unable to calculate rather than no fuel being used. A DSG  may be different but in my manual petrol car lifting off completely doesn't shut off the supply of fuel to the engine - as the engine doesnot cut out if I depress the clutch -its running at idle. 

2 hours ago, thamestrader said:

 A DSG  may be different but in my manual petrol car lifting off completely doesn't shut off the supply of fuel to the engine - as the engine doesnot cut out if I depress the clutch -its running at idle. 

 

It will shut the fuel off - all cars have done that for years.  The engine management system stops it from stalling when you depress the clutch.

I dislike this coasting. If I pick the eco mode it does this. I never use the sport mode either. Mine is left on the normal mode all the time. I did play around with these modes in the first few months of owning the car. I get the best mpg, according to the trip computer, in normal mode not using the cruise and leaving the gearbox to its own devices. Occasionally I will use the manual via the flappy paddles, but that is rare. Why buy an auto to change gears yourself? I have a 22 year old golf gttdi for changing gears!

Quote

I dislike this coasting. If I pick the eco mode it does this. I never use the sport mode either. Mine is left on the normal mode all the time.

 

On earlier cars, coasting was only active in ECO mode, later cars e.g my 2021, coasting is active in all except Sport mode. Presumably this was done to fiddle (improve by a gnats) the WLTP figures in Normal mode

58 minutes ago, NottsIan said:

 

On earlier cars, coasting was only active in ECO mode, later cars e.g my 2021, coasting is active in all except Sport mode. Presumably this was done to fiddle (improve by a gnats) the WLTP figures in Normal mode

 

 

Hmmm

 

On my other DSG's (Fabia, Yeti, Passat) coasting mode has been a separate selection.

 

On our MQB Octavia coasting only in Eco.

 

On my late 2023 Karoq 1.5TSi (Evo2 DXDB engine) I.m sure I only get Coasting in ECO?  

I don't think my MY19 1.0 SE tech DSG has the coasting facility, but going downhill, it wants to stay in top gear and so their is little engine braking.  Not quite coasting but a good 2nd best and I quite like this.  If I want to slow, I use the brake.  All my previous auto cars, including a 1.2 DSG Yeti, have wanted to change to a lower gear on anything but moderate downhills, which hasn't often been what I'd want to do.

 

From past posts here, I recall the Karoq 1.5 DSG without coasting is differently set up to the 1.0 DSG and wants to drop down for downhills, like most other auto cars on the road.

5 hours ago, logiclee said:

 

 

Hmmm

 

On my other DSG's (Fabia, Yeti, Passat) coasting mode has been a separate selection.

 

On our MQB Octavia coasting only in Eco.

 

On my late 2023 Karoq 1.5TSi (Evo2 DXDB engine) I.m sure I only get Coasting in ECO?  

 

Generally only use Normal in our early 22 1.5TSi Karoq and it coasts.   Not only does it coast, but it seems to roll remarkably freely - it'll go considerable distances without slowing much.    After it being selectable on our Tiguan I was bemused that it's not selectable in Kaorq - you're just stuck with it.

Quote

On my late 2023 Karoq 1.5TSi (Evo2 DXDB engine) I.m sure I only get Coasting in ECO?  

and your'e right @logiclee my new 2024 1.5TSi only coasts in ECO.

On 07/12/2024 at 15:45, NottsIan said:

and your'e right @logiclee my new 2024 1.5TSi only coasts in ECO.

 

That would be an improvement, I would prefer to turn it off, if I could.

I do prefer the "natural" in-gear slowing down rather than the slight "runaway" feeling I have with coasting.

From the various responses I get the impression that the  “coasting” implementation differs between models and years, as people’s experiences are different. In my 2023 2.0 TSI coasting only results in a speed increase on definite slope, it can occur in normal or Eco modes but only from very low rpm. If I am accelerating and lift off it won’t coast.

I’m still trying to fully understand this coasting mode. Yesterday I did a120 mile round trip with a 20 minute stop before returning. On the outbound part coasting kicked almost everytime I eased off on the throttle, e.g. when approaching slower vehicle in front or for a bend. On the return coasting wouldn’t engage for about 20 miles and then starting working as I’d expect. I’d like to understand what it is that affects whether it engages. I think it has something to do with the current throttle position and a gradual lift.

Never worries me. If it does that's fine, if not then that's fine too. Life's too short..