[Darren69]

In my experience with my S4 and 748 too for that matter, they just don't need regular plug replacement assuming that the Efi is set up correctly. I'm still on the original set in the S4 when I bought it 10 years ago. It is regularly serviced by Cornerspeed and I quizzed Neil and he said they were fine. So as long as it starts and runs fine I wouldn't worry. The only ignition related running issues I have had in those 10 years is a faulty coil stick and an intermittent crank sensor.