kobelco sk95ur wont rev

I have a 1990 Kobelco sk95ur serial number YX-00116, the engine wont move from idle it is like it is limp mode all the linkages appear to be ok , the electrically actuated cable doesn't appear to pull tight , also there is two toggle switches under the seat that I am also after a genuine workshop manual for this machine

any help would be much appreciated

tim