I have a zanussi fl-1081 washing machine with sticking timer?

Zanussi FL-1081, the timer gets stuck on some but not all programes, I have replaced the timer and door switch, cleaned and checked the pressure vessel 6 months ago it it worked fine upuntil now. I stripped and cleaned the pressure vessel again, checked all parts but it still fails to operate properly.
I am reluctant to buy a new machine as everything on the fl-1081 seems ok apart from this.
Please help!!