Need an accurate TDC indicator for silly idea #3478

[dnb]

I'd like to convince VEMS to give me a signal at TDC for cyl 1.  (or indeed any cylinder really) 
Does anyone have any idea how to achieve this simply? 

I have no spare coil, injector or stepper outputs, but do have a couple of P259 output spare (the tacho & shift light outputs)

Thinking about it, it really doesn't have to be an output from VEMS - anything would do, even putting the dizzy back in my engine with the advance locked.  The only snag with that is that there isn't space for the dizzy any more!

Whatever happens, the method needs to be fast reacting, accurate, reliable & easy to do...  (I don't want much, do I? ;) )

[Jorgen]

I guess that this will be used for some kind of diagnostics?

I'm afraid that it's hard. Even with custom code it's not easy to do as all your ignition capable outputs are used up.

Maybe it's simplest to fit a 1GT101 Hall sensor that senses something on the front pulley? This would be the most stable solution if it's used for diagnostics.

Jörgen Karlsson
Gothenburg, Sweden.