I disconected the battery last night and took it today for a 100 km drive in town and it only dropped the revs to about 500RPM 3-4 times. Before this, the revs dropped much more frequently.
Still this isn't right and if someone knows a cure i'd really appreciate it.
PS. tomorrow i'm going to test everyting on tech 2 and maybe i can find something there.
Cheers !