I'm still marvelling at how smart DSG is particularly when it comes to over-run and the way it changes down to save on brake wear and tear. I was talking ot my brother-in-law who recently bought a Passat which appears to have the same engine/DSG as mine. He swears blind that on a downhill slope, if he blips the accelerator, the car shifts to neutral as long as he isn't touching the accelerator or brake. My first reaction was to say 'rubbish' but I have a long history of being wrong about things. Am I in this case? I was always taught that coasting was a no no. Perhaps with all the microprocessor control over stability and such that modern cars have, it's no longer an issue - I wonder.

It sounds like my Tiguan. You could set it to "freewheel" as your brother-in-laws Passat. However there is no such facility on my new Yeti DSG.

I have to say there were several posts as to whether it saved any fuel at all!

Ohhh.... so he was right then and I have to notch another 'wrong' up 8^)

 

One of my very early cars a Rover 90 IIRC had a huge knob on the dashboard which you could turn when in gear and pulling to switch to freewheel. A bit lethal when driving in autopilot mode if you habitually relied on overun for light braking. Made me jump more than once after forgetting I'd put it on but seeing as it's the car doing the thinking and concentrating nowadays I suppose it's not as risky.

 

I wonder what other differences there are between his car and mine, we both keep finding new things.

Probably not worth it as coasting in neutral involves fuel for idling whereas in gear its zero till back to idle revs.

Rye's comment is correct and the reason why many on the Tig forum reckoned you used more fuel using the coasting function! I tried it many times an found psychologically you saved fuel but practically you couldn't tell the difference apart from a feeling of lack of control until you got used to it.

On the plus side it was better than the system on the old SAAB 96

The theory that in certain situations coasting in neutral will save you more fuel... you travel further using less fuel rather than being on over-run and slowing down too much just to have to use the throttle again.

I'm not 100% certain on this, but I believe you can enable the coasting option on the Yeti in VCDS...

Probably depends on the controller that's fitted.

I have simply shifted into N on some occasions and then back to D after without any shift shock sensation at all but just figured zero consumption on a trailing throttle is already a fuel saving measure.

The loss of the 'potential' energy was offset by idle consumption.

It's a return to the old days when coasting was a transmission feature of Rovers and Riley's etc I seem to recall.

This goes a bit against the grain for me, I remember the first NEW car I had, a Wartburg Knight Estate that had a free wheel (being a two stroke if you closed the throttle the engine got no lubrication!) but not very good brakes.   

It did make me very aware of the traffic and road in front of me though. 

When I changed to a DSG I was worried that there would be no engine braking but, in practice, it feels very under control.

 

Fred 

I could be wrong be even on over run I would have thought that some fuel must be used just to keep the cat up to temperature which probably means it makes no measurable difference

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I could be wrong be even on over run I would have thought that some fuel must be used just to keep the cat up to temperature which probably means it makes no measurable difference

Sent from my GT-I9300 using Tapatalk

Both our cars show zero on a trailing throttle

I believe I am correct in saying that when engine braking, and no throttle input, the fuel is shut off completely and the engine is only using the momentum of the car to keep it turning over. That is why the consumption shows ---

I believe I am correct in saying that when engine braking, and no throttle input, the fuel is shut off completely and the engine is only using the momentum of the car to keep it turning over. That is why the consumption shows ---

So you still get engine braking, whereas what you really want is free wheeling (for economy). In a DSG + electronic throttle you'd have thought they would have a touch of the brakes to engage engine braking...

So you still get engine braking, whereas what you really want is free wheeling (for economy). In a DSG + electronic throttle you'd have thought they would have a touch of the brakes to engage engine braking...

That would seem logical to me too - touch of brake to engage the engine and a touch of accelerator to free wheel. In mine it's almost like that except it doesn't free wheel at all and it needs more than just a touch of the brake to get the car to drop a gear and *really* use the engine for braking.

If you have a car with a DSG box then just drive it in different situations and see what it does, and maybe try other cars and other DSG or a

S-Tronic and see what they do, 

some very weird stuff is talked about with some that are clueless about them, even people that drive them.

I've read somewhere (there it is, Google) Audi A6 frinstance has 'freewheel mode', and, as above, it would be very simple to activate based on whether you are using either pedal or none.

I bet it'll be at least available on the new Yeti at some stage.

So you still get engine braking, whereas what you really want is free wheeling (for economy). In a DSG + electronic throttle you'd have thought they would have a touch of the brakes to engage engine braking...

No. It's been said so many times before... Freewheeling-coasting uses fuel to keep the engine running.

Using engine braking provides momentum to turn the engine over so no fuel is required.

Thus engine braking is more economical.

I'm not 100% certain on this, but I believe you can enable the coasting option on the Yeti in VCDS...

Coasting is an option that can be enabled/disabled in the DSG Yeti, as soon as the brake pedal or accelerator is pressed coasting is disabled.

No. It's been said so many times before... Freewheeling-coasting uses fuel to keep the engine running.

Using engine braking provides momentum to turn the engine over so no fuel is required.

Thus engine braking is more economical.

Not that simple as the engine braking has a resistance that slows you down more than if you were just coasting.

According to Zf on their 8 speed auto there is a 3% improvement in economy due to the coasting, although I'm not sure if this is just through the transmission or the whole vehicle.

In my experience, coasting is only good in theory as there are so many instances that mean you have to use your brakes at the end, as opposed to zero fuel consumption and zero brake wear (never factored in as a 'cost').

There is usually a need to slow; traffic, intersection, roundabout, blind bend etc and for me, no braking via pedal or fuel consumed is preferable compared to idling fuel and brake costs.

The question is where can you find a long straight road downhill that won't involve some sort of speed reduction at the end?.

To me it's more about theory than real world conditions.