Outer Limits 4x4 Board

i have a gq swb TB42 auto. and iv started to have problems with it. stuff like, intermittant trouble code (116) not shiting corectly. (as in driving on flat road at 100 and power light randomly flashing on and off with no change of accelerator pedal) have changed oil no change.
any one have any ideas whats going on? had this problem befor?? any help would be good
cheers Tom.D.