Clutch wear index low

Xav76

New Member
Messages
9
Hi all,

I own a 4200CC from 2005 and a launch x431. My gearbox version is CFC231. The clutch wear index value I read is 460 with a PIS of 5.4mm. Time to time I feel some slippage when changing gear, mainly in mountain at high motor rev. I reduced the PIS to 5.2mm, behavior is better and the wear index went down to 400. This value looks really low compared to the target that should be around 4000.

Do you know if there’s a scale factor to apply on the value from x431? Or any other idea?

Thank you
Xavier
 

Gp79

Member
Messages
1,489
Are you not supposed to reset the wear index when adjusting the PIS?

So wear index back at 4000 then see where it moves after tweeking the PIS.
 
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Xav76

New Member
Messages
9
I updated the PIS already from 5.4 to 5.2 and the wear index moved from 460 to 400. It has not been reset to 4000.
 

spkennyuk

Member
Messages
6,145
I updated the PIS already from 5.4 to 5.2 and the wear index moved from 460 to 400. It has not been reset to 4000.
Your PIS is still way out. Set it to 4.65 and go from there.

Before you change the PIS make sure the car is fully warmed up and done plenty of gear changes.

Put the car on a level stretch of road and then adjust the PIS to 4.65. Then do a gear relearn.

Once you have done that engage 1st and take your foot off the brake but dont touch the throttle. If there is any creep of the car then adjust the PIS upwards to say 4.70.

If you have the launch diagnostic you can also look at the live data for the primary gear your looking for the live data to show zero when your in 1st gear without touching the throttle and then change to showing data numbers as soon as you touch the throttle. If the live data shows numbers in first without touching the throttle you clutch is dragging and you need to increase the PIS setting. Work in 0.05 increments when fine tuning the PIS.
 

Xav76

New Member
Messages
9
I reduced the PIS to 4.7 and run a self relearn + reset wear index with the x431. Gearbox behavior seems very good, no slipping and clutch no dragging in 1st idling. But Clutch Wear Index still around 400. I think it’s not reliable
 

spkennyuk

Member
Messages
6,145
I reduced the PIS to 4.7 and run a self relearn + reset wear index with the x431. Gearbox behavior seems very good, no slipping and clutch no dragging in 1st idling. But Clutch Wear Index still around 400. I think it’s not reliable
What version number of the maserati software on the launch are you using ?

If the launch software version is an older one then there were some bugs in the software. If i recall correctly version 11.15 still had some bugs in the TCU module. For example you could only change the PIS setting to 1 decimal place and the clutch used reading also showed incorrectly as the formula used was incorrect.

It could well be that your on an early version of the launch maserati module and its reading the clutch wear index as 400 instead of 4000.
 
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Sam McGoo

Member
Messages
1,952
I reduced the PIS to 4.7 and run a self relearn + reset wear index with the x431. Gearbox behavior seems very good, no slipping and clutch no dragging in 1st idling. But Clutch Wear Index still around 400. I think it’s not reliable
I wouldn't read too much into that wear index number. It's too far out to be correct. Much likelier that the software has just dropped a 0, which would then make it pretty accurate.

The fact you've put the PIS back to recommended level and now the car drives correctly, I'd say that was you're problem.

On my x431, for the Granturismo, I have to jump between software between the GT F1 software and the F599 software (301). When doing the PIS, the GT software gives me a value of 335, which doesn't make sense to me, but when on the 599 software it states eg 4.3mm which does. So if you find a value that doesn't make sense, have a flick through the other F1 software to see if one does.