OK - Thought I'd report back my findings. Not entirely successful (or conclusive), but there is an end note....
Vehicle: 2.0 JTS Selespeed 02 reg
Software used: DnEcuDiag 18.104.22.168 (but also FiatECUScan 3.5 at one point) with ign at MAR, engine off.
Problem encountered straight away - What Gearbox ECU did I have?
When connecting DnEcuDiag (Alfadiag) I had 2 options, the CFC208F and CFC218F. Both would connect and would seem to give the same readings, with one important exception; the 'Clutch Actuator Position'
. When connected as the 208F it read 28.39mm but when connected as the 218F it read 17.58mm - Big problem if it was that!
Having read around a bit more it would seem that the 218F is only applicable to the GTA, so I could be confident that the 208F was what I should be using
(Note: While I was still a little unsure as to what ECU to use I connected using FiatECUScan and this came up with only one option, the 208F. However, it refused completely to actually connect as I kept getting 'No ECU Response', although it would connect everytime to the Engine ECU. No idea why this was the case as it has connected previously. Anyway, gave up on that eventually as I had already found my answer to the ECU question and Alfadiag was doing a fine job otherwise)
Right, back to my readings.
I have selected the few which I thought(?) were important with regards to this problem:
Hydraulic Circuit Pressure
The hydraulic pressure would very slowly drop to around 48 after about 5 minutes but opening the door caused it to rise back to around 55 within a minute or so.
Position of Insertion Fork
(no idea what this does or whether important!)
Reference Position Clutch Actuator
(again, no idea)
Actuators > Calibration Routine - Clutch Calibration
I couldn't perform this as the diagnostic failed every time it was selected! Didn't note down what it said but it just gave a load of error coding which meant nothing to me.
On intial connection there were two fault codes on the system:
I cleared these and at this point in time haven't investigated further, that's toinight's job!
So, my initial thoughts from this investigation.
It would seem to me that the hydraulic pressure is good and holding so I think my belief that the accumulator or pump being defective is incorrect. It would also seem that the clutch rod length is fine.
Now I'm stuck!
While doing this I managed to run the battery down (I'm sure it's not a battery problem as this was changed just a few weeks ago and it did take me a long time to figure out what I was doing
- no surprise the battery went dead on me, especially with the radio blasting out!). This means I haven't had chance to see what effect my own changes have made (see below).
As everything mechanical seemed to check out, it suggested to me that this odd behaviour could be an electrical problem. I am considering replacing the Gearbox ECU but whilst rummaging around I also wanted to check underneath for a potential wiring/sensor problem. This is because the gear change problem is much more frequent in the wet (but by no means soley happening in the wet). There was a sensor which I believe to be the 'gearbox input shaft sensor'
] that had no cover on which left it somewhat exposed, but it didn't apparently have any other damage. This is right at the bottom and an obvious candidate for water ingress. I have removed the sensor and it checked out fine. I have put a new cover on it now and am waiting to try it.
Hope that's been of some help to others but I'm still stuck - as it stands I've no idea what has been causing my problems!!
I will report back when I've been able to give it a run again but in the meantime would welcome any (ANY!!) suggestions as to what I should do next.