Selespeed calibration issue

Started by warsch, August 28, 2017, 02:26:42 PM

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warsch

I decided to do an annual selespeed service.

Which entails fluid level check, clutch rod adjustment and calibration.

So I checked the fluid and it's fine, adjusted the clutch rod by a little bit. Then ran a clutch drain. However, when I ran EOL (in AlfaOBD) or final calibration (in FiatECUScan) selespeed error pops up roughly 45 seconds in. There are no errors in ECU right after, the only suspicious thing is low pressure - 34-35 bar. Can that be the reason? Does that mean the accumulator is on its way out?

The internet told that one of the ways to complete calibration is to plug the pump on with a cable for a few short bursts to pump the pressure. Is it a good or a bad idea?

Also, another question is about clutch self-calibration. I followed the instruction in FiatECUScan (i.e. something like start it, than start engine, stop engine, start again and pull off in 2nd gear up to 3000 rpm). I did that but how do I know it worked?

In the end, I'm quite happy with the result as the clutch became somewhat smoother especially when pulling off in the 1st gear. 

Citroënbender

The flat sphere definitely wouldn't be helping. I have an idle fantasy of adapting the Selespeed unit to fit a Citroën style accumulator, pressure adjusted to 55 Bar. 

If you fitted a Tecnosir brand regassing valve to the Citroën sphere, you wouldn't even need to take it off the gearbox to check or adjust...

psproule

Usually it's the pressure drop that triggers it to stop the routine. If the battery is a bit tired and / or the pump is a bit slow it might not be able to keep up with the demands of running the calibration. I have a 20A battery charger that I just hook up when this happens and it seems to work fine. Could also be that your accumulator is tired.

You are correct in that you dont get any notification on the clutch learn success. It's a bit frustrating. I have always wondered if it does anything much however recently after some major work the clutch felt awful in it's engagement and running the routine sorted it out. You need to follow the instructions to the letter though including checking the coolant temp is above the minimum.

Pat

bazzbazz

#3
Quote from: psproule on September 13, 2017, 09:14:58 PM
I have a 20A battery charger that I just hook up when this happens and it seems to work fine. Could also be that your accumulator is tired.

FOR GODS SAKE NEVER DO THIS !!!!  You risk the chance of blowing one or more of the computers.

No disrespect intended Pat, you are one of many who try to help out when they can, and are to be commended for it, it is just that people do not realise just how risky it is to do such a thing. I have had to repair many an Alfa just because the Road Side Assist Mech was sloppy when fitting a replacement battery. To connect the system to the pulse of most Hi amp chargers, and the effect it has on the supply signal to the computers is a bit like you walking around with a defibrillator attached to your heart !   :o

As for the original posting - the problem is usually caused by either the accumulator on the way out, or most likely the System Pressure sensor, or even a combination of both.

I would suspect the pressure sensor as it should not allow the system to drop below 45 bar. Quick test, with the car in the driveway, engine off, key at MAR, you should get 2-3 gear changes before the pump kicks in. If it changes with every gear change the accumulator needs changing.

And there is a listing for the Clutch calibration success for most models, it is in the parameters section.
On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

warsch

So the driveway test showed that the pump kicks in after 1 or 2 gear changes. What do I do re accumulator? First, how urgent is that? Second, do I have to buy brand new accumulator? Can I go with reconditioned? And what kind of price am I looking at part wise?

Citroënbender

They cannot be practically reconditioned, the filling valve is more or less riveted shut. A clever tinkerer could - I'm sure - fit a serviceable filling valve, they would then need a large nitrogen cylinder and test equipment. It's the same sort of problem faced with the Citroën C5 suspension spheres.

It's simpler for most people to buy a new accumulator, they are (from memory) sub $200 now. Try EAI for new, from my experience the Sydney branch usually has stock and will post promptly. I would not delay it, that's risking either gearbox shutdown or synchro damage.

Just because I love hydraulic systems in cars (might be informative)...
http://www.rrsilvershadow.com/ETechn/Hydr/Compaccum.htm

warsch

I'm sorry, but what's EAI? Is it this http://www.eai.net.au/ ?

If it's around $200 for a new one, I'll just do it.

Citroënbender

That is they. I prefer to deal with the Sydney office.