Flat spots and hesitation o 730d anybody experienced this E65

Hi Folks
I have a NEW (well 8 months old) E65 730d SE UK version with the 238BHP turbo diesel + Auto.
The power and torque is phenomenal compared to my old E38 740i but there is a
persistent flat spot or hesitation when pulling away from a rolling start.
Example..... When cold no problems as I feel that the extra fueling on a cold engine covers this problem but when hot try to picture this.
30 mph lift of the throttle and on the over-run let the car slow to a reasonable speed to say exit a side road or when rolling up to the entry to a round-a-bout (not many in the US) and if the way is clear floor the gas pedal and NOTHING............... then Varoooooom! with neck snapping acceleration!
Now my theory is that on the over-run the fueling is cut off to lower emissions and aid fuel consumption. This will, in effect, reduce the exhaust flow to the turbocharger and slow it down so no boost. When I floor the pedal it take some time - say a second or two to get the turbo spooling up and Varooooooom!
Off we go again.
Has anybody experienced similar situations?
Anybody got any ideas that might cure this trait in such a lovely car? Sir Hugh of Bognor
--
I used to be an Egotistical Meglomaniac - but now I'm just perfect!

Hugh Gundersen
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R. Mark Clayton wrote:

Remedy - try a manual change to see if he's right!
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Diagnosis wrong and totally misleading. The fuel is not cut during downshifts only on the over-run and then until the vehicle reaches a constant speed or the throttle is touched.
Problem caused by "adaptive" driving learning mode of transmission system. If one drives like a granny then the system behaves like a granny. My problem was that the vehicle had been driven as a demo for 3 months before it was shipped to the South Coast from Inverness in Scotland which is not race track country and demos do not usually include a bit of drag racing and drifting.
Had the computer system cleared and rebooted today (free) and it feels like a different car --------- next is DDE reprogramming and a throttle response adaptor.
Sir Hugh of Bognor
--
I used to be an Egotistical Meglomaniac - but now I'm just perfect!

Hugh Gundersen
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We may not have a race track in Inverness but we have lots of lovely twisty and empty roads ;-) If you're ever up here I'll show you a few......
I'll have a word with the boys in Calterdon (our local dealer) to spice up the test drives a bit ;-))

Glad it's fixed :-) Modern cars are too clever for their own good.
--
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Email: snipped-for-privacy@unixnerd.demon.co.uk, John G.Burns B.Eng, Bonny Scotland
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wrote:

Hi John
Spoke with you the other year about a few oddities with my old E38 (email) 740i.
They seem like nice guys at Calterdon but the delivery driver nicked 1/2 tank diesel on the way down. Still they sent me a nice cheque to cover it.
This 730d is very nice - the only reason I got it from Calterdon is that they accepted my ridiculous offer and shipped it free. The car is loaded, TV, Sun glass, auto this and auto that and might just wipe my backside if I asked it too!
Performed faultlessly touring France this summer 2.5K miles up to Andorra as well (the E38 did that marvelously too).
Couldn't wait for the new 735d with the twin turbo engine so will probably get it chipped (reprogrammed to 289BHP0 and might get one of those throttle response thingies too - know anything about them - bit new and seen lots of mentions but no tests or trials......... weird!
Sir Hugh of Bognor
--
I used to be an Egotistical Meglomaniac - but now I'm just perfect!

Hugh Gundersen
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I've not read much about it either. Sounds like the perfect car though. I was dissapointed to hear that a 335d can only be ordered with an auto gearbox in the uk.
Calterdon are generally pretty good. The head sales guy is a bit of a 2002 fan :-) The have a cat that seems to have adopted them, it gets Whiskas twice a day in return for keeping the mice down :-))
I have memories of drooling over a 2000 touring in their old showroom when I was about 9 years old.
--
Who needs a life when you've got Unix? :-)
Email: snipped-for-privacy@unixnerd.demon.co.uk, John G.Burns B.Eng, Bonny Scotland
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wrote:

With the amount of torque available you don't need a manual otherwise you would be forever changing gear. The power band is so flat and strong 1200 - 3500/4000 the 6 speed (with manual over-ride and paddle button for up/down shifts) auto makes it seem one gear and with a CLEAN auto-box computer like mine is now it would learn how mad you were and adapt as mine is doing (straight jacket on order). Actually when thinking about the 335D it is quite reminiscent of driving a dragster - foot down and no gear changes to top speed..............................Varooooooooooooom!

--

Sir Hugh of Bognor

The difference between men and boys is the price of their toys.
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wrote:

John
The throttle response adaptor - apparently a load of crap for 200+
This Greek guy claims to hold the patent
http://www.sprintbooster.gr/en /
And this guy has written a "white paper" (technical) about it and it kind of confirms my theory that it is simply an amplifier and does nothing more than a heavy right foot would do.
http://bipesauto.com/sprintbooster
Well worth a read and possibly a download for posterity
Sir Hugh of Bognor
--
I used to be an Egotistical Meglomaniac - but now I'm just perfect!

Hugh Gundersen
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Have to agree, have just holidayed in my X5 around the highlands - based from Inverness - and had great fun with the car :)
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