I am not sure if mine have ever been done? I have 100,000km or 60,000 miles and I don't seem to have start issues, I do have a bit of black soot but I chalk that up to catless down pipes and a white vehicle. I have a tune and it seems to pull like a freight train
I was thinking about getting injectors, spark plugs and coil packs all done but I have a feeling that would be several thousand dollars and likely only "needed" because I spend too much time reading on forums