gidday guys ,my 1987 shorty is a sd33 turbo and has got 380 000 on the clock some times when i drive it it goes hard <for a diesel> then other times its like sluggish could this be due to the amount of ks on it or should i shout it new injectors ? its my first diesel i have ever owned not sure if this is commen with diesels as my other 4bee is petrol injected 4.2 and its got **** loads of balls.