Attesa Failed During Launch At Drags

[Remix-]

Hi there,

Last night at the drags I experienced a failure with ATTESA. I was hovering around 7.5k for a launch, dropped the clutch only to sit there with my rear wheels spinning! I backed off the throttle briefly and then put foot back down on the accelerator only to slingshot down the track with awd working correctly. Any ideas why this could be happening?

There was no warning lights on my dash (although I believe this might have been disconnected as I do not get a warning light after plucking the fuse out for rwd).

Appreciate any help guys.

Edited March 23, 2006 by Remix-

[saliya]

check that the warning light globe is working by switching ignition to 'on' without starting the car...

Regards,

Saliya

[RNGTR]

Maybe the transfer case is worn out???

Time for a rebuild if so.

[djr81]

Hi there,

Last night at the drags I experienced a failure with ATTESA. I was hovering around 7.5k for a launch, dropped the clutch only to sit there with my rear wheels spinning! I backed off the throttle briefly and then put foot back down on the accelerator only to slingshot down the track with awd working correctly. Any ideas why this could be happening?

There was no warning lights on my dash (although I believe this might have been disconnected as I do not get a warning light after plucking the fuse out for rwd).

Appreciate any help guys.

Attessa doesn't remove wheel spin. To a degree it can only react to the inputs you are putting in.

To be honest unless you are running drag radials of some description 7500 is too many revs. I used 6000 to launch at the last hillclimb which was plenty - and that with more weight on the rear wheels & with R compounds tyres on a stinking hot day.

[Remix-]

Hi there, I am aware of how Attesa is designed to function and that slight wheel spin is the norms.

Let me elaborate on my circumstances - After dropping the clutch I sat in the same position for a couple seconds not moving (I felt no front torque) from the starting line.

My rear wheels were spinning wildly and without any intervention from the front wheels at all (Attesa is designed to intervene around this time).

I backed off completely (ie no throttle at all), put my foot down again and attessa cut in immediately just as quickly as it cut out previously. I ran higher than a 3.0 60ft as a result of my excessive rear wheelspin.

This was my 5th run of the night (my previous 4 runs were fine and I was consistently netting 1.9 60fter's without problem).

Cheers,

Lyndon

Edited March 23, 2006 by Remix-

[Remix-]

Maybe the transfer case is worn out???

Time for a rebuild if so.

Cheers for the reply RNGTR,

Due to the nature of Attesa cutting out so suddenly (as I had no problems hard launching earlier), I would assume that if it was a transfer case wearing/worn out that it would slip gradually rather than suddenly? (please correct me if I am wrong guys).

Edited March 23, 2006 by Remix-

[Marlin]

REMIX- I had this exact same issue with my 32 GTR a few years back, and after about a year of searching, it turned out to be excessive resistence in the earth wire running from the body near the engine bay fuse box to the engine block (driver's side). My actual earth cable required replacement, but maybe yours has just a dicky connection or dirty contact? I suspect the issue may be amplified by the engines requirement for plenty of spark at the same time as tryin to engage the front end? Worth a look maybe?

Cheers.

[VB-]

a build up of air in the ATTESA system? from memory this would cause the front wheels to be very slow to engage, maybe even a couple of seconds. normally wen u go around a corner and put the boot into it, would the front torque split engage immeadiately? watch the guage for the torque split, see how quick it is to respond next time, or if it climbs real slowly. might need to give the system a bleed. i may be totally rong here, this is just off the top of my head, so if i'm rong, please correct me

[Remix-]

Great replies, cheers guys.

This weekend I will check ATTESA diagnostics and see what comes up.

Marlin I will also check the ground wire you mentioned (any chance you could post a photo of the ground wire location?).

If I am still unsuccessful - bleed ATTESA time.

Edited March 23, 2006 by Remix-

[Marlin]

Great replies, cheers guys.

This weekend I will check ATTESA diagnostics and see what comes up.

Marlin I will also check the ground wire you mentioned (any chance you could post a photo of the ground wire location?).

If I am still unsuccessful - bleed ATTESA time.

Sorry mate, I don't have the car any more, but it's really simple to find, it's the only large diametre earth on the driver's side (approx 8mm dia.)...... runs from in front of the right stut tower to the right engine mount normally.

Cheers.