A couple of possibilities that strike me:
- perhaps I originally had the gap too small; the sensor has been smacked around by the wheel and it now won't work unless the gap is small (gap is now 0.55mm and it's not happy with it any wider and the daub of paint I put on its tip has already been worn off with the quick test). Do I just need to order a new one from DIYAutoTune?
- maybe running the sensor at 12V rather than 5V would allow me to run a bigger air gap
- change to a different hall effect or reluctor sensor that allows a bigger gap
- tear the engine down and replace the mains (and much else no doubt)
Appreciate any suggestions or advice.
FWIW, running MS2/Extra on a V3 board. 4 cylinder 2.2L Peugeot. 36-1 wheel, standard dizzy and coil. Very mundane, but gets along nicely all the same.
Have fun,
Rob.