If the DMF has any Play my Advice would be to renew it, had Problems as my Car was new (Vectra C 2.2 Elegance) and switched to get you home Mode. The Dealer had it for one Week to find the Fault. Had just a new one fitted incl. new DMF the old one showed a very small Amount of Play after 50.000 Miles. The Dealer charge House prices for it .