sorry I am late on this thread but..
I have a 2001 2.0 147 selespeed and spent the first 2 years battling with similar error messages and problems. Now it is fixed!
ABS failure, VDC failure, selespeed failure, engine failure. Car would stall at traffic lights - grrrrrrrr and not restart. Sometimes would not change gear at the worst moments. Would get stuck in 2nd or 3rd. Would get stuck in 1st when trying to start the car so the car was dead and stuck in my garage and could not even be pushed out top tow to the agents. Would not restart on hot days. Wait 10 mins or so and restart and it would usually be fine for a few days. Every problem would be fine again after turning engine off and restarting. Never failed when the fu@k*ng agents looked at it!
After changing the gearbox, brake pedal switch, hydraulics, clutch, wiring loom, selespeed pump and much else on the car over a frustrating 2 year period when it would come back to me after weeks in the workshop and run fine for a few weeks then start all over again with problems. Each time they lent me a fiat or nissan while they "fixed it". The last time I got the sales managers new Alfa 2.6 sportwagen as a loan. I told them they could keep my 147 and I would keep their car
. They finally fitted a new main computer (which I had said was the real problem in the first place but they refused to believe me!) and it is now 9 months totally problem free.
My Alfa experience was not good, but now I am finally happy with a reliable car at last.
Most of the problems experienced here with Selespeed, ABS, etc failures are probably due to a rotten computer (Italy was never good at electronics or software)
Make them change the computer!