Second question,

Has anyone experienced a little hesitation or skip when cornering at low speed from a 4x4 yeti?

On what type of surface?

All surfaces I think but mainly low speed 1st or 2nd gear 90 degree bends. Very odd but doesn't do it on straights through those gears.

I wondered if the Haldex cuts in as the front diff splits wheels speeds?

All surfaces I think but mainly low speed 1st or 2nd gear 90 degree bends. Very odd but doesn't do it on straights through those gears.

I wondered if the Haldex cuts in as the front diff splits wheels speeds?

 

4 X 4 diff? Tyres the same state of wear on all four wheels?

Edited 3 January, 201610 yr by bigjohn

So we don't have different wheel speeds to go round corners then?? Tyres are all the same condition also.

Edited 3 January, 201610 yr by Cricster

Does the esp flash at all?.

I'll check that.

Second question,

Has anyone experienced a little hesitation or skip when cornering at low speed from a 4x4 yeti?

 

 

Yes.

 

It's been raised many times before on here with no definitive conclusion.

 

Personally, I think it's the Haldex kicking in.

 

if you find a condition when it occurs, repeat it at very slow speed and it seems absent.

 

My view is that when the Haldex senses a combination of sensor readings, it tightens up rapidly. Ie, if you speed up from a standstill on full lock, the sensors, throttle angle, ABS etc, pre-empt a potential traction loss and take action to minimise traction loss.

 

if you floor it, the sensation ( hesitation) is lost in the general "fuss" of everything kicking off!!

 

Like Graham, I spend a lot of time on gravel/ mud, and I've experimented with friends watching the wheel "action"    

 

Just my 2p's worth.

Edited 3 January, 201610 yr by Yety

Yes I have experienced the slight hesitation a few times. It initially worried me, but only happens for a very very short time. I have not found a place it repeatedly occurs, but it is usually on corners. I thought it was something to do with the slight turbo lag, as you are usually slowing down around the corner and then push the accelerator just before the corner end, when the turbo is presumably spinning slowest??

I'm with Yety on this, its been mentioned before and something I've noticed.

IIRC one suggestion was that the Haldex is actually engaged by default when pulling away from rest, and the slight 'shunt' may be occurring when it disengages as the car gains speed, with the effect being magnified/made detectable because of the large difference in rotation speeds between the nearside and offside rear wheels when negotiating a tight turn.

 

One proposed way to test this was to disable the Haldex by pulling its fuse (not sure which one that is), and repeating the manoeuvre which typically triggers the effect.

Yes, it's very occasional and very subtle. Read about it before on this forum. Is it just a Yeti thing or also on Oct Scout and Superb? Not concerned about it, just accept it as a very minor quirk.

As long as it's not broken I'll then move onto my next q.

Thanks for info.

As long as it's not broken I'll then move onto my next q.

Thanks for info.

Midlands

Wet weather?

Damp clutch-packs- snatch

If it's still doing in summer dry weather it's not that then.

Got 12 months on it so summer it is.

Thanks

IIRC one suggestion was that the Haldex is actually engaged by default when pulling away from rest, and the slight 'shunt' may be occurring when it disengages as the car gains speed, with the effect being magnified/made detectable because of the large difference in rotation speeds between the nearside and offside rear wheels when negotiating a tight turn.

That's exactly what I think it is.

 

The Haldex 4 clutch pre-engages when pulling away from standstill.

When turning a tight corner (such as turning out of a side road or parking space), the input to the front diff will be turning faster than the input to the rear diff as the front wheels take a wider path - yet the Haldex clutch is engaged and tying the two diffs together.

What gives ?

The front and rear couplings of the propshaft are made of rubber - so presumably these take some of the strain, perhaps the various rubber engine mounts, suspension mounts etc also do to some degree.

But the Haldex clutch soon disengages as there's no hard acceleration or wheel slip to warrant its use.

When it does - all that tension is suddenly released, and I reckon that's the thump that we feel.

 

Could probably log it in VCDS, IIRC there's a measuring block in the Haldex controller that shows %age clutch engagement; so long as the update rate was fast enough and you could safely watch it, you might see if the engagement figure drops at the same time as the thump is felt.