X5 xDrive40D fuel economy

[acideraser]

Owner's manual also warns that two-wheeled vehicles might not be detected. Be careful!

Thinking this over suspect system works like that to make sure people use this mostly in the motorway and not in city traffic.

[535dboy]

[quote=""acideraser""]
That's a low blow BMW, i dont know what to do now, maybe I should exclude this feature and get 4.0d engine instead....

[/quote]

I'm saying nothing at this stage

[X5Sport]

I actualky opted not to have ACC or Lane Departure Warning because I was worried that I might take an eye off the ball just for a moment, but the wrong moment, and have the technology drive me into trouble.

This radar system really ought to be able to react to a sharp down-doppler indicating a stationary object in its path and sound a chime and at least put the brakes on. That is a real simple thing to do in software, and so obvious, and the system is already using that data to keep speed & distance anyway. How did BMW miss that one? Similarly it ought to be able to use the information from the on-board gyros to control the acceleration around a corner, not just whack the car up to the Cruise setting again. I don't know what the road conditions were at the time and I know the M25/M11 junction well, but on a wet day you could get into serious trouble very quickly with unfortunate consequences.

Perhaps this is why Belgium bans the use of Cruise Control on motorways.

[SimonD]

This is obviously a fundamental design "feature", not a bug. The reason? I'll guess that the radar is tracking many stationary objects coming towards you all the time (overhead gantries, road signs, stopped cars in other lanes), and to eliminate "noise", the software has to simply ignore ALL stationary objects, otherwise it would have to interpret what they are and if they are a threat. Place a disclaimer in the user guide to prevent litigation, and you have a system that provides some [limited] benefit.

Also, the radar's maximum range appears to be about 200 meters. Not sure the car could stop in that distance (it works up to 120 mph) if it detected a static object. Would you really let software activate a full blown retina detaching emergency stop on the GUESS by the software that that object was a potential threat and predict that you'd keep the steering wheel in a straight line for the next 4 seconds (i.e. plan to hit it intentionally)? Doubt any manufacturer would sanction software that would provide this function.

Other manufacturers only seem to provide an up to 30 mph City Safety system for the above reasons, I'm guessing.

Still a great system if you keep alert.

[acideraser]

well too late to change spec now, car is going in production . This system should definitely improve mpg and also make longer motorway trips easier. In the end of the day BMW is driver's car and driver has to pay attention all the time.
Thank you again SimonD for detailed explanation how ACC works

[MJim]

@SimonD - my understanding is that the active cruise never applies emergency braking, rather it applies more moderate brakes and alerts the driver who can then stamp on them if considered appropriate. Although still waiting for my X5 so going on other's advice ....

[Smatty]

[quote=""Iainm""]I'm averaging between 35.8 and 37.4mpg

AMD will remap it as will DMS!! Mines booked into AMD [/quote]

How are you achieving this, in an E70

[chetalien]

[quote=""Smatty""][quote=""Iainm""]I'm averaging between 35.8 and 37.4mpg

AMD will remap it as will DMS!! Mines booked into AMD [/quote]

How are you achieving this, in an E70 [/quote]

thats amazing, have u remapped it?

[petert]

Never been anywhere near this figure in a 6 speed 35d. I reckon 32 to 33 on the OBC is about as much as I can get and I am pretty gentle with the right foot.

Peter T

[SimonD]

Just recorded my best consumption figures yet : 630 miles from one £119 tank of fuel. Average of about 33mpg. Now at 6500 miles.

[jason@bwchiptune]

We offer remaps for the 40d for £399 to forum members only
Normal price is £599
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