japie:
The injection moment is in sync with the engine trough an alternator, I have a pcb with 4 IR transmitters on it and one with 4 receivers, between those there is a rotating plate with a little hole so at every TBP one of the receivers gets a pulse.
I don't know what a TBP is. When you say alternator, do you mean the alternator that provides electrical power for the vehicle? How is that connected to the crank?