I suspect it is programmed in to prevent left foot braking from loading up the torque convertor / transmission.
Potentially I am identifying a common nuance with the D4, and whilst I think it’s dangerous I wanted to understand how people “drive” around the problem. If I touch the brake at any point whilst my foot is also on the accelerator the car hesitates for 2-3 secs (seems like an eternity) then clear itself and accelerates. I know the hesitancy problem has been discussed before, but I am trying to establish whether it’s all the same thing.
The problem for me is based on my motorsport background I am a left foot braker, as well as when 4wding proper technique would be using both feet to operate both pedals it tight and difficult situations. Likewise when in carparks or reversing up driveways or trailers I find using the on and off method with left and right foot, gives much better control of the car. Problem is the minute there is even a slight cross over the car hesitates for those few seconds hence either removing control from you, or placing you in a dangerous situation in the middle of traffic (has occurred a few times).
Is this a characteristic of the D4 and live with it, or is it something that can be improved? For me it’s very odd, even after 10k’s of driving it, and I hazard a guess is actually a behavioral aspect of the ZF 6 speed?
Welcome any input or thoughts.
Thanks
JB
I suspect it is programmed in to prevent left foot braking from loading up the torque convertor / transmission.
could also be a crash prevention technique,
i.e. jamming your foot on the brake and half on the accelerator in an emergency by accident, therefore it cuts the accelerator.
maybe
 ForumSage
					
					
						ForumSage
					
					
                                        
					
					
						Long story as to 'why'... but I'm relieved to see another driving technique heretic ! I find it safer in traffic - shorter reaction time and more control when reversing.
My Classic's 4 spd ZF does'nt do any of the above, so I'd guess its a function of the engine/gearbox management systems, such as the programming engineers never forseeing such sacrilege. But then again, mine's a technological dinosaur compared to D3/4....
Or a glitch...
 Fossicker
					
					
						Fossicker
					
					
                                        
					
					
						I understand that (probably wrong) when you press the brake, the CAN bus tells the ECU to ignore all accelerator input...at least that is what happens with my diesel VW.
This could explain why you see this effect. However I frequently "drive through the brakes" when offroad, so suspect it is speed sensitive, or terrain response sensitive.
It is a characteristic of the car - designed to act that way.
LR's philosophy is that the electro/mechanical aids in the vehicle do not require the use of simultaneous braking and acceleration whilst off-roading. There is no requirement to "overload" the diffs due to the TC/TR, and HDC/DSC takes care of the rest.
Cheers,
Gordon
Mine's a 2012 D4 six speed and I haven't seen this "delay" at all. I don't normally use left foot braking, but have done occasionally in tight parking / manoeuvring situations, and have also been known to occasionally sit at the lights with left foot on the brake and right foot with slight pressure on the go pedal for quick get-away. Have never noticed any delay or similar issues when doing this.
Cheers .........
BMKAL
[QUOTE=superquag;1959226] I find it safer in traffic - shorter reaction time and more control when reversing.
QUOTE]
It's actually the correct way to drive and something that is not taught to the masses, yet funnily enough is in hi performance and skid pan driving techniques. Application of the brake can shift weight transfer, steady a car, balance before braking, or provide a gradual weight shift rather than sudden when undertaken correctly, even whilst accelertaing. It actually becomes a habit.
I actually left foot brake in a manual, except for when coming to a stop.
Much safer in traffic, cuts reaction time by over 50%, I find it very useful in carparks, and when in busy intersections and you need to react quickly. trying to reverse the car last week with a tonne of wood in the back up a hill proved quite difficult as I had to balance the cars movement on the accelerator whilst in a tight position.
Thanks Gordon, makes sense then from a 4wd perspective however on road even the slight brush of the brake at the wrong time Proves to be quite dangerous. I have actually done it by accident and have been left stranded in the middle of the intersection. I am not “loading” the brake and accelerator at the same time, actually it’s a smooth transition between the two, the cross over in most circumstances is nil, however the movement between two pedals seems to need a particular amount of gap between the two (approx 1 sec)
 Wizard
					
					
						Supporter
					
					
						Wizard
					
					
						SupporterIf its happening a lot with minimal overlap it could be that the brake light switch is on the way out. This is the first symptom that there is a problem with the switch and after a whle the car finally spits the dummy and won't drive at all because it thinks the brakes are on.
When it starts failing it usually manifests as a delay when turning corners after removing your foot from the brake, even for right foot brakers like me.
Bob
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