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My new car (see here (http://www.cleanmpg.com/forums/showthread.php?t=32377)) will have VAG's Auto Start/Stop feature, so during short stops (e.g. traffic lights), if you put the (manual) gearbox into neutral and lift the clutch pedal, it cuts the engine.
Depressing the clutch to put it into 1st causes the engine to be automatically started up again and then you move off as usual.

I tried this a few times during the test drive and it worked really well, although I found it eerily quiet sitting there without an engine purring away. :)

Anyway, I'm wondering if anyone who has a car with this system (e.g. Bluemotion or Ecomotive owners) has tried putting the car into neutral whilst coasting?
I'm wondering whether the engine stops in such circumstances or does the Auto Start/Stop only kick in when the car is stationary, for safety reasons?

And on the subject of FAS on manual non-hybrids generally - when you cut the engine using the key - does the power steering and power braking still function properly?

I'm not familiar with your particular vehicle (and we have no non-hybrids available in the States at all with auto-stop) but I've read that a number of such models only stop the engine if the vehicle is at a stand still. I seem to recall that there was one that would turn off the engine when in gear if no pressure was applied to the gas pedal but I believe that was a DSG equipped vehicle and it probably shifted to neutral on the fly.

I'll be very interested to hear what you discover on this front!

As for FAS in a non-hybrid, if the power steering is hydraulic you'll lose it. If it is electric, it may cut out briefly but should come back (there are some oddities with this in Mazdas, though). Power braking relies upon vacuum "accumulated" (not quite right when speaking of an absence of something!) from the running engine so it will last a bit until the reservoir is "exhausted." In most vehicles this should be 3-4 full presses of the brake pedal... but you should try it somewhere deserted to find out for sure. The vacuum is only used while the brake pedal is being moved so you'll use it faster by pumping than you will by just using constant pressure. After the vacuum is gone you can still stop the car but it won't be with power assist. Make sure you know what this feels like and expect it so that you never rear end someone!!

If you try this, please PLEASE get to know your vehicle somewhere secluded and never EVER coast with the key in anything other than the "ON" position for any significant distance. Flip it out just long enough to get the engine to die and then put it back. Air bags and ABS are just two of the items that won't be functional if the key isn't in the ON position, and some vehicles engage a steering lock in the ACC position.

If you try this, please PLEASE get to know your vehicle somewhere secluded and never EVER coast with the key in anything other than the "ON" position for any significant distance. Flip it out just long enough to get the engine to die and then put it back. Air bags and ABS are just two of the items that won't be functional if the key isn't in the ON position, and some vehicles engage a steering lock in the ACC position.

Also, a LOT of cars don't run the odometer unless the key is all the way to ON. You can be racking up miles, but have them not show up - bad when you try to do MPG math by hand!

OK, good tip about making sure the key is in ON even if the engine's not running, thanks. :)

I'm 99% sure the steering is "electromechanical power assisted" or summat like that. I'm sure I read it in the specs.

Sounds like FAS (with a key) is something to maybe try on an empty road only when I'm very accustomed to the car...

I've been trying to practice DWL on the country roads (rollercoasters!) near where I live on the drive to and from work. It's amazing how much more efficient it is just slowing down a little on the way up, at least if the car's MPG indicator can be believed.

Any other techniques that aren't too tricky to learn, that I could practice in my current (DSG equipped) car? ;)

Yes, you can believe your built in gauge -- DWL can save a very large amount of fuel.

I'd try coasting in neutral and consciously using deceleration fuel cut for those circumstances you have to slow down to kill fuel usage and save your brakes. You can keep it in fuel cut longer by downshifting to keep the RPM up over the required threshold.

Learning to coast in N and getting used to switching in and out will prepare you for learning to P&G... but I wouldn't do that until you have a gauge to see what's going on. Your built in gauge might be sufficient (if you have an average mpg set-able by trip?), but get used to when the correct times to coast are first.

You may have to experiment. I did and came up with something that works far better then what was suggested on my Honda Fit. I installed a momentary switch that stops the fuel pump. I needed that as if I cycled the ign switch it stopped the ele power steering and was unsafe.
Using that helped me get some nice gains over P&G W/O fas

I don't have a recent diesel with stop/start system :-(

On my old turbo diesel I can confirm that :

the key in ACC will lock the steering wheel as soon as you move it
the odometer accumulates distance only on ON, not on ACC
the power steering is off when the engine is off, which you do feel under 30 mph

Also when you bump start, the power steering wheel will activate immediately and will make you over turn if you aren't in a straight line.

I only know about the stop/start system from Citroen which is available only on gasoline. It switches off the engine under 4mph when the break pedal is pushed. As soon as the break pedal is released, the engine is restarted.

Denis.