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Ah... interesting info red devil and oldtamiyaphile. I didn't know that about TDi turbos.
I did once experiment with Pulse n Glide, though not with Engine Off Coasting. I found it didn't work for me at all well. A constant speed gets me way more mpg.
The way I drive this TDi, the turbo is almost never doing anything. I monitor boost pressure from time to time, and it's not zero, but pretty close.
Typical use of Engine Off Coasting for me is long straight shallow descents on motorways and dual carriageways, and on those roads my normal cruising speed is between 40mph and 50mph. At those speeds the turbo is pretty much idling. (On single carriageways I tend to keep my speed a little higher as it is more dificult for other drivers to overtake.)
Another occasional use of EOC is on local roads where for example along one stretch I happen to know that I can coast a mile or so and maintain the speed limit of 30mph. Again, no significant turbo boost going on prior. On those urban/suburban roads with a 30mph limit I typically sit at 27mph in 5th gear at engine tickover (800 RPM). At that speed on the flat I'm getting stupidly high mpg - like 140 or so - but still a mile of EOC can really boost my average up.
My car is relatively heavy, and normally is loaded down with work tools, and my feeling is I get best mpg when I can keep at a lowish speed and never slow down or accelerate.
One thing a mechanic once advised me - and this I do - is to blast the **** out of the engine once a week. Just for 30 seconds I'll accelerate up a hill, just to get the turbo spinning. The mecahnic reckoned that with the way I drive I could otherwise have problems with vanes sticking (I don't know what vanes are really, but lets not allow them to stick, eh?)
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