I've been playing around in the 4x4 in the wet and greasy conditions we're having at the moment, with ESP on and off.

To be honest if you are driving hard or in a hurry it seems better with the ESP off in the wet. What do other 4x4 owners think ?

I don't know how the computers controlling the haldex 4x4, ABS and ESP work together, but I reckon the ESP / traction control is too easily confused.

Example - floored in second (on a very wet road) it seems to cut the power, notice that I've still got the pedal mashed, let me accelerate then cut the power again. I've also seen what happens on slight lock from a standing start and hard in 2nd through roundabouts (where you would expect stability to count), and I still go for ESP off.

So is it me or am I missing the point here ?

It just seems more consistent and predictable leaving the 4x4 side to work things out without the ESP pitching in.

Can someone with experience of this please help explain ?!

Thanks :confused:

Interested to hear replies, I too am somewhat perplexed as to the on/off option.

Originally posted by Fabpreza in this post

Example - floored in second (on a very wet road) it seems to cut the power

"It seems"? There would be a flashing light, so you'd know!

Can't it be the way the ECU is programmed? Flooring it in 2nd from low revs - and I mean really flooring it - would perhaps have the ECU jump into a failsafe mode, dropping the turbo's pressure.

I have found that applying the throttle more precisely works for better acceleration than flooring it. Haven't had the light come on once, incidentally, and since I've managed to learn the trick I've had the tail slide out quite a few times the past days - which apparently is passable for the ESP, as long as you catch it!

I agree, with ESP on you can't really predict what the car will do. So consistency is definitely lost, and if you're used in a driving style where you expect the car to perform based on its physics, then ESP is not your friend.

Stuck in sand.

ESP on: first gear in, cluch not pressed, engine reving at 2000, car not moving (needless to say cluch smells terribly).

ESP off: releasing the cluch suddenly, engine stops running (as expected). Releasing the cluch slowly and the car gets clean off the sand.

But that's in the manual too (i.e. don't use ESP when stuck in sand).

When driving in the limit though, and in the beatiful (not) greek tarmac that is as slipery as soap, with ESP off you can have a beautifull drift at any speed (i.e power oversteer). With ESP on, you get a weird reaction where the car behaves as if my wife drives it (she can't ).

So what to do with it I hear you asking. Well, with our roads, ESP is good for safety. It wont let you drive in the limit, and if you try it will make the car steer like a train. Thankfully there's this button you can use to disable it and drive a car that behaves like one

Otheos, so there is someone else up at this silly hour on a Sunday, Im meant to be working but just taken a short break

What you say sort of seems to make sense, I think I will need to experiment further with the ESP swithed off, just need to find a big area of tarmac for my first "experiments"

Stuart

Lol, I was about to go fishing and thought I'd check the forum first (so much of rural lifestyle ).

Agreed,

Although so far in 6-8 Months of driving I don't really care to turn it off. I quite like the reaction and thus counter reaction effects on greasy roads, although carefull throttle applications for the situation rarely provokes it into life. However your all right in never quite knowing whats going to happen

Now the summer is here I will be turning it off; so far it's really as Otheos satates great for safety, standing water, hard breaking on non matched surfaes, greasy roundabouts etc.

But as the roads dry out it's need will be negated. In fact just yesterday I had the pleasure of seeing my esp light up half way up a hairpin curve...

Perhaps with ESP it means that you have to have Extra Sensory Perception to know what's going to happen next ?

The ESP correcting and your instinct (much slower my instinct than the computer) is fun! Oooh understeer, correct; arh esp has beaten me to it, too much, react and so on....perhps this is why I need to remove the body role, must look a sight...

Might go and try my local private road with esp off...well it has to stop raining soon.

Ok now I am confused.

Sat at wet, greasy junction, ESP off. Floored it, massive wheelspin and had to lift off the accelerator to regain forward motion.

I can't work out why the power wasn't just transferred to the back wheels.

I obviously need driving lessons or some ideas before next winter !

I obviously need driving lessons or some ideas before next winter !

I couldn't have put it better myself!

Perhaps a read of the Owner's Manual as well while you are waiting for Father Christmas?

Owners manual it is (does it have a section for 220bhp owners ?), but on that experiment I'll give it a 5/10 and my previous 4x4 Subarus and A4 quattros a 9 or 10/10 for wet weather standing traction.

This is most bizzare! Will try it tonight, bound to rain. I would not of thought ESP disabled the haldex, was it a clutch hold start or handbrake start? Handbrake on disables the haldex, maybe it will not reengage if under stress?

All of the above is guess work!

Colin - I agree, it is strange but much to DGW's amusement !

I'm beginning to genuinely wonder if the haldex isn't working properly.

This was waiting on the level to join a roundabout (Not sure if handbrake applied - possible prior to launch). I've owned a lot of 4wd cars and never had this sort of experience apart from on sheet ice.

Normally if you boot a 4x4, you get a second's worth of wheelspin (at the worst) and you are then shot down the road as the power is transferred between the four wheels. This felt like only the front wheels were involved with the full torque !

Open to your experience and advice - gratefully received.

When it was remapped they said that the 4x4 seemed lazier than normal kicking in on the rolling road.

Are you supposed to do anything with the ESP button on the rolling road.

I should be going to the ro-road at the weekend so will see what's happening.

Well Ian's 4x4 was fighting to get off the rollers, so maybe a ecu fault, eek.

Well it's rained, so I'll test at lunch, really no problem at all

Lazier? Well haldex says it takes less that 10 degrees of front wheel spin before the rear axle is engaged so I guess the only lazyness added by the extra horse power is how fast those 10 degrees take to revolve (faster than the 10ms the valve on the haldex takes to fully open and engage) lol

However they cover it too, saying that the engagement is not affected by wheel speed (although based on the 10ms valve opening time there is a top limit -do the maths please ).

As for front wheels spinning on starting on water, that's more like the Scenic and other silicon clutches where starting stuck causes the rear axle to remain unengaged (beats me why but it does).

On a test between the Volvo XC70 (haldex) and the Scenic, the Volvo was clearly able to get away from starting in mud (lots of it) while the Scenic stood there spinning it's front wheels forever.

Keep your views , test techniques or fault-finding suggestions coming.

I'm going to try letting some air out of the tyres next

:confused:

I think of it more as a "correction" tool for altering the line of the car mid corner, than any form of "launch" control - it's not great for allowing "full bore" acceleration out of tight bends like the hairpin at Curborough, but is handy in the wet at speed.

I tend to leave it on if dry, cos if I get it to trigger I'm being a hooligan, but turn it off in the wet if the surface is "playful".

Thanks for that on ESP. I'll leave it on.

Any ideas on the unexpected launch wheelspin ? Took me by surprise.

Well, even in snow (fresh powdery not hard packed \ ice) I had to turn ESP off and really boot it to get wheelspin, same goes for oil, I have spotted it and knocked ESP off for "launch".

I often turn ESP off if I want a quick "flick" out of a junction etc in the wet, can only think that it did not know "which way" to help you if the steering was dead ahead?

ESP is to remove understeer \ oversteer, so I suppose if all four wheels had equal grip, and the wheel was dead ahead, and the yaw sensor did not detect any lateral movement, it would let the wheels spin?

oh, and RE haldex handling on RR, Jabba used about 6 straps all around mine as I was paranoid, and indeed on full throttle you could see the car lurch a bit as it threw power front and rear to try and get grip, guess it saw it as an incredibly slippy surface.

It does it's best to climb out, think ESP was on but not activated, as steering wheel \ yaw sensor agreed I guess.

I wish you guys would stop writing all this interesting stuff - I'm mean't to be doing my tax return !

As a non tecchy - could I ask whether the loss of traction could be nothing to do with the ESP but the rev. limiter ........

if you floor the pedal , the free revving engine soon hits 6000 + rpm - now on the road if you suddenly overtake in 3rd for example , keeping your foot right down , one finds that you are suddenly without power ?????? ........ creating the same situation as from a standing start .......

A chipped 4x4 certainly runs out of revs very quickly in first, tis angry and very short, tend to "get it moving" with gentle first, then full throttle in second. Full throttle in first tends to result in head interfacing with windscreen as you hit the limiter!

I went out trying to replicate yesterday's 'fun' but - surprise suprise - it behaved itself (ESP on).

As it felt just like a front wheel driver with 220bhp yesterday (ie no fun from rest in the wet!), is there any way that I could inadvertently have used that handbrake trick to disengage the 4x4 ?

That makes the most sense to me as an explanation (unless there had been diesel dumped on the road under the rainwater).

Well I thought as it's raining properly this morning I'll try it at every junction....

ESP off!

Most I got no wheel spin atall, most were straightish junctions, mergers.

However the one junction which is notorious for wheel spin (left hand on a slight slope, normally greasy)

Booted it off I went, fronts began to slip, a bit more slip, the wheel spin sound then revs rose and then bam was sent hurtling forward...ALL in a very very short space of time!

So what went on...ESP is off! Normally that junction gunning it in the wet as I do alot actually because we can is with ESP on, never get any spin or sensation of it. That said I actually enjoyed the play, certainly later on a small roundabout that is one of the few without suregrip it was mucho fun.

But it's a strange moment, sensing that front spin then propulsion again. I was not concerned by the spin as it went almost as soon as it came. It was the raising of revs, as a front wheel drive car would do given it's friction has just disapeared, but then coming back under control as the power I guess went to the back and then restored to the front...

Does this help or confuse, more testing Fab! m8.

As per Ian I tend to leave ESP on in the dry and wet just to catch any issues in cornering, especially roundabout surveys.